Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2016	Oct. 31, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3
Trading Symbol	MRAM
Entity Registrant Name	EVERSPIN TECHNOLOGIES INC
Entity Central Index Key	0001438423
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		12,498,128

Condensed Balance Sheets - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 1,999,000	$ 2,307,000
Accounts receivable, net	2,326,000	1,909,000
Amounts due from related parties	619,000	564,000
Inventory	5,303,000	4,176,000
Prepaid expenses and other current assets	467,000	190,000
Total current assets	10,714,000	9,146,000
Property and equipment, net	1,705,000	1,654,000
Intangible assets, net	33,000	132,000
Deferred offering costs	3,101,000	0
Other assets	50,000	29,000
Total assets	15,603,000	10,961,000
Current liabilities:
Accounts payable	2,095,000	1,162,000
Accrued liabilities	3,114,000	1,755,000
Amounts due to related parties	6,771,000	3,812,000
Deferred income on shipments to distributors	1,646,000	1,440,000
Derivative liability	120,000
Convertible promissory notes payable-related party	8,461,000
Current portion of long-term debt	3,904,000	1,175,000
Total current liabilities	26,111,000	9,344,000
Redeemable convertible preferred stock warrant liability	405,000	437,000
Deferred revenue	42,000	229,000
Long-term debt, net of current portion	4,914,000	6,739,000
Total liabilities	31,472,000	16,749,000
Commitments and contingencies
Redeemable convertible preferred stock, $0.0001 par value per share; 77,080,000 and 68,080,000 shares authorized as of September 30, 2016 and December 31, 2015, respectively; 2,486,199 shares issued and outstanding; aggregate liquidation preference of $64,642	64,642,000	64,642,000
Stockholders' deficit:
Common stock, $0.0001 par value per share; 204,000,000 and 175,000,000 shares authorized as of September 30, 2016 and December 31, 2015, respectively; 3,025,920 and 3,015,281 shares issued and outstanding as of September 30, 2016 and December 31, 2015, respectively	0	0
Additional paid-in capital	10,620,000	9,301,000
Accumulated deficit	(91,131,000)	(79,731,000)
Total stockholders' deficit	(80,511,000)	(70,430,000)
Total liabilities, redeemable convertible preferred stock and stockholders' deficit	$ 15,603,000	$ 10,961,000

Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Redeemable convertible preferred stock, par value	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized	77,080,000	68,080,000
Redeemable convertible preferred stock, shares issued	2,486,199	2,486,199
Redeemable convertible preferred stock, shares outstanding	2,486,199	2,486,199
Redeemable convertible preferred stock, liquidation preference, value	$ 64,642	$ 64,642
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	204,000,000	175,000,000
Common stock, shares issued	3,025,920	3,015,281
Common stock, shares outstanding	3,025,920	3,015,281

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Product sales (including related party sales of $662 and $902 for the three months ended September 30, 2016, respectively, and $1,396 and $2,739 for the nine months ended September 30, 2016 and 2015, respectively)	$ 7,008	$ 6,671	$ 19,731	$ 19,108
Licensing and royalty revenue	156	421	299	638
Total revenue	7,164	7,092	20,030	19,746
Cost of sales	2,859	3,458	8,563	8,689
Gross profit	4,305	3,634	11,467	11,057
Operating expenses:
Research and development	3,111	5,081	14,342	14,723
General and administrative	1,586	1,634	4,881	5,208
Sales and marketing	788	1,198	2,476	2,652
Total operating expenses	5,485	7,913	21,699	22,583
Loss from operations	(1,180)	(4,279)	(10,232)	(11,526)
Interest expense	(798)	(231)	(1,982)	(414)
Other income (expense), net	534	1	814	10
Net loss and comprehensive loss	$ (1,444)	$ (4,509)	$ (11,400)	$ (11,930)
Net loss per common share, basic and diluted	$ (0.54)	$ (1.77)	$ (4.40)	$ (4.67)
Weighted-average shares used to compute net loss per common share, basic and diluted	2,657,574	2,552,185	2,589,704	2,552,185

Condensed Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Related party sales	$ 662	$ 902	$ 1,396	$ 2,739

Condensed Statement of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Condensed Statement of Cash Flows - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities
Net loss	$ (11,400)	$ (11,930)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	598	1,073
Loss on disposal of property and equipment	80
Stock-based compensation	520	301
Change in fair value of redeemable convertible preferred stock warrant liability	(32)	(17)
Change in fair value of derivative liability	(798)
Non-cash interest expense	1,066	178
Compensation expense related to vesting of common stock	751	1,027
Changes in operating assets and liabilities:
Accounts receivable	(417)	509
Amounts due from related parties	(55)	(91)
Prepaid expenses and other current assets	(277)	(387)
Inventory	(1,127)	(1,513)
Other assets	(21)	(10)
Accounts payable	598	267
Accrued liabilities	204	(493)
Amounts due to related parties	2,959	2,563
Deferred income on shipments to distributors	206	(153)
Deferred revenue	(187)
Net cash used in operating activities	(7,332)	(8,676)
Cash flows from investing activities
Purchases of property and equipment	(596)	(978)
Net cash used in investing activities	(596)	(978)
Cash flows from financing activities
Proceeds from convertible promissory notes-related party	8,500
Proceeds from debt	1,500	8,000
Payments on debt	(598)	(3,000)
Payments of debt issuance costs	(40)	(130)
Payments on capital lease obligation	(179)	(179)
Payments of deferred offering costs	(1,611)
Proceeds from exercise of stock options	48
Net cash provided by financing activities	7,620	4,691
Net decrease in cash and cash equivalents	(308)	(4,963)
Cash and cash equivalents at beginning of period	2,307	9,624
Cash and cash equivalents at end of period	1,999	4,661
Supplementary cash flow information:
Interest paid	916	237
Non-cash investing and financing activities:
Purchase of property and equipment under capital lease obligations	34	440
Issuance of warrants with debt		$ 307
Deferred offering costs recorded in accounts payable and accrued liabilities	$ 1,490

Organization and Nature of Business	9 Months Ended
Organization and Nature of Business	Sep. 30, 2016
Accounting Policies [Abstract]
Organization and Nature of Business	1. Organization and Nature of Business Everspin Technologies, Inc. (the “Company”) was incorporated in Delaware on May 16, 2008. The Company’s MRAM solutions offer the persistence of non-volatile memory with the speed and endurance of random access memory (“RAM”) and enable the protection of mission critical data particularly in the event of power interruption or failure. The Company’s MRAM solutions allow its customers in the industrial, automotive and transportation, and enterprise storage markets to design high performance, power efficient and reliable systems without the need for bulky batteries or capacitors. *Reverse Stock Split* In September 2016, the Company effected a 1-for-26 reverse stock split of all outstanding shares of the Company’s capital stock, including common stock and redeemable convertible preferred stock. All share, option, convertible promissory notes, warrant, and per share information presented in the condensed financial statements has been adjusted to reflect the stock split on a retroactive basis for all periods presented and all share information is rounded down to the nearest whole share after reflecting the stock split. *Initial Public Offering and Concurrent Private Placement* On October 7, 2016, the Company’s Registration Statement on Form S-1 (File No. 333-213569) relating to the initial public offering, (“IPO”), of its common stock was declared effective by the Securities and Exchange Commission (“SEC”). Pursuant to such Registration Statement, the Company sold 5,000,000 shares at an initial public offering price of $8.00 per share for net proceeds of $37.2 million to the Company, net of underwriting discounts and commissions, but before offering costs. Concurrent with the IPO, the Company issued 625,000 shares of its common stock in a private placement for net proceeds of $4.7 million, after deducting the placement agent fee.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2016

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2015 has been derived from the audited consolidated financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company’s consolidated financial information. The results of operations for the three and nine months ended September 30, 2016 are not necessarily indicative of the results to be expected for the year ending December 31, 2016 or for any other interim period or for any other future year.

The accompanying condensed financial statements should be read in conjunction with the audited financial statements and related notes thereto for the year ended December 31, 2015 contained in the Company’s prospectus filed pursuant to Rule 424(b) under the Securities Act of 1933, as amended, with the SEC on October 7, 2016.

Use of Estimates

The preparation of the condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, fair value of assets and liabilities, inventory, income taxes, redeemable convertible preferred stock and related warrants, common stock, and stock-based compensation. Actual results could differ from those estimates and assumptions.

Concentration of Credit Risk

Financial instruments that potentially expose the Company to a concentration of credit risk consist principally of cash and cash equivalents that are held by a financial institution in the United States and accounts receivable. Amounts on deposit with a financial institution may at times exceed federally insured limits. The Company maintains its cash accounts with high credit quality financial institutions and, accordingly, minimal credit risk exists with respect to the financial institutions.

Significant customers are those which represent more than 10% of the Company’s total revenue or gross accounts receivable balance at each respective balance sheet date. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable, net are as follows:


	Revenue												Accounts Receivable, net
	Three Months Ended September 30,						Nine Months Ended September 30,						As of September 30,			As of December 31,
Customers	2016			2015			2016			2015			2016			2015
Customer A		22	%		27	%		23	%		26	%		16	%		28	%
Customer B		*			20	%		*			12	%		21	%		23	%
Customer C		11	%		12	%		11	%		14	%		*			*
Customer D		*			*			*			*			11	%		*

*	Less than 10%

Deferred Offering Costs

Deferred offering costs, primarily consisting of legal, accounting, printer and other direct fees and costs relating to the IPO, are capitalized. The deferred offering costs will be offset against the Company’s IPO proceeds during the quarter ended December 31, 2016. As of September 30, 2016, the Company capitalized $3.1 million of deferred offering costs on the condensed balance sheet. No costs were capitalized as of December 31, 2015.

Fair Value of Financial Instruments

The Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The hierarchy gives the highest priority to valuations based upon unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to valuations based upon unobservable inputs that are significant to the valuation (Level 3 measurements). The guidance establishes three levels of the fair value hierarchy as follows:

Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Inputs (other than quoted market prices included in Level 1) are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.

Level 3—Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

The carrying value of accounts receivable, accounts payable, and other accruals readily convertible into cash approximate fair value because of the short-term nature of the instruments. The carrying value of the Company’s variable interest rate debt, excluding unamortized debt issuance costs, approximates fair value. The Company’s financial instruments consist of Level 1 assets and Level 3 liabilities. Where quoted prices are available in an active market, securities are classified as Level 1. Level 1 assets consist primarily of highly liquid money market funds that are included in cash equivalents. Level 3 liabilities consist of the redeemable convertible preferred stock warrant liability. Generally, increases or decreases in the fair value of the underlying redeemable convertible preferred stock would result in a directionally similar impact in the fair value measurement of the warrant liability.

The following table sets forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands):


	September 30, 2016
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,017	$	—	$	—	$	2,017

Total assets measured at fair value	$	2,017	$	—	$	—	$	2,017

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	405	$	405
Derivative liability		—		—		120		120

Total liabilities measured at fair value	$	—	$	—	$	525	$	525


	December 31, 2015
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,354	$	—	$	—	$	2,354

Total assets measured at fair value	$	2,354	$	—	$	—	$	2,354

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	437	$	437

Total liabilities measured at fair value	$	—	$	—	$	437	$	437

The following table sets forth a summary of the changes in the fair value of the redeemable convertible preferred stock warrant liability, a Level 3 financial liability, which is measured on a recurring basis (in thousands):


Balance at December 31, 2015	$	437
Change in fair value recorded in other income (expense), net		(32	)

Balance at September 30, 2016	$	405

The key assumptions used in the Black-Scholes option-pricing model for the valuation of the redeemable convertible preferred stock warrants were:


Expected volatility		42.4 – 52.0	%
Risk-free interest rate		1.22 – 1.86	%
Expected term (in years)		4 – 9
Exercise price	$	26.00
Dividend yield		—	%

The following table sets forth a summary of the changes in the fair value of the derivative liability, a Level 3 financial liability, which is measured on a recurring basis (in thousands):


Balance at December 31, 2015	$	—
Issuance of derivative liability		918
Change in fair value recorded in other income (expense), net		(798	)

Balance at September 30, 2016	$	120

The Company estimates the fair value of the derivative liability using a with- and without-model and the probability-weighted expected return method, which estimates a discounted value based upon analyses of various future outcomes, such as an equity financing with proceeds greater than $5.0 million, an IPO, a merger or sale, and staying private. The with- and without-model calculates the value of the Company’s convertible debt with the features being evaluated for separate accounting, and an identical instrument without those features. The outcomes of each scenario in the probability-weighted expected return method are based upon a market multiple approach, that involves various market multiples and projected financial information, as well as option-pricing models, to reflect optionality within features of the convertible debt instrument. The change in fair value is recognized as a gain or loss in the other income (expense), net line on the statements of operations and comprehensive loss. See Note 8 for additional information regarding the derivative liability in connection with the convertible promissory notes.

Redeemable Convertible Preferred Stock Warrant Liability

Warrants for shares that are contingently redeemable are classified as liabilities on the balance sheet at their estimated fair value because the shares underlying the warrants may obligate the Company to transfer assets to the holders at a future date under certain circumstances such as a deemed liquidation event. The warrants are subject to re-measurement at each balance sheet date and the change in fair value, if any, is recognized as other income (expense), net in the statements of operations. The Company will continue to adjust the liability for changes in fair value until the completion of the IPO in October 2016, at which time all redeemable convertible preferred stock warrants were converted into warrants to purchase common stock and the liability was reclassified to additional paid-in capital.

Derivative Liability

The convertible promissory notes contain certain redemption features that meet the definition of a derivative. The redemption of the convertible promissory notes upon an equity financing with proceeds in excess of $5.0 million and in the event of an IPO are contingent redemption features that are not clearly and closely related to the debt instrument and have been bifurcated and recognized as a derivative liability on the balance sheet as of September 30, 2016. The derivative liability is subject to re-measurement at each balance sheet date and the change in fair value, if any, is recognized as other income (expense), net in the statements of operations and comprehensive loss. The Company will continue to adjust the liability for changes in fair value until the earlier of: (i) maturity of the convertible promissory notes; (ii) the completion of an IPO; or (iii) the completion of an equity financing with proceeds in excess of $5.0 million; or (iv) the optional conversion into Series B preferred stock. Following the completion of the IPO in October 2016, the Company will revalue the liability prior to the conversion of the promissory notes and then will no longer adjust the liability for changes in fair value.

Revenue Recognition

The Company recognizes revenue when the following criteria are met: persuasive evidence of an arrangement exists; the price is fixed or determinable; delivery has occurred and title passed; and collectibility is reasonably assured. For sales to OEMs and contract manufacturers, this occurs generally upon shipment. Provisions for product returns and allowances are recorded in the same period as related revenues. The Company analyzes historical returns, current economic trends and changes in customer demand and acceptance of product when evaluating the adequacy of sales returns and other allowances, which are netted against accounts receivable, as these are processed as credits against future purchases or balances outstanding.

The Company sells the majority of its products to its distributors at a uniform list price. However, distributors resell the Company’s products to end customers at a very broad range of individually negotiated price points. Distributors are provided with price concessions subsequent to delivery of product to them depending on their end customer and sales price. These concessions are based on a variety of factors, including customer, product, quantity, geography and competitive differentiation. Price protection rights grant distributors the right to a credit in the event of declines in the price of the Company’s products. Under these circumstances, the Company remits back to the distributor a portion of their original purchase price after the resale transaction is completed in the form of a credit against the distributors’ outstanding accounts receivable balance. The credits are on a per unit basis and are not given to the distributor until the distributor provides information regarding the sale to their end customer. Revenue on shipments to distributors is deferred as the price is not fixed or determinable until delivery has been made by the distributor to its customer and the final sales price has been established.

At the time of shipment to distributors, the Company records a trade receivable for the selling price as there is a legally enforceable obligation of the distributor to pay for the product delivered, inventory is reduced by the carrying value of goods shipped, and the net of these amounts, the gross profit, is recorded as deferred income on shipments to distributors on the balance sheet. The amount of gross profit that will be ultimately recognized in the statements of operations on such sales could be lower than the deferred income recorded on the balance sheets as a result of credits granted to distributors from the price protection rights. The Company is unable to estimate the credits to the distributors due to the wide variability of negotiated price concessions granted to them.

Thus, a portion of the “deferred income on shipments to distributors” balance represents the amount of distributors’ original purchase price that will be credited back to the distributor in the future. The wide range and variability of negotiated price concessions granted to distributors does not allow the Company to accurately estimate the portion of the balance in the deferred income on shipments to distributor accounts that will be credited back to the distributor. Therefore, the Company does not reduce deferred income on shipments to distributors or accounts receivable by anticipated future price concessions rather, price concessions are recorded against deferred income on shipments to distributors when incurred, which is generally at the time the distributor sells the product.

At September 30, 2016, the Company had $2.7 million of deferred revenue and $1.1 million of deferred cost of sales recognized as $1.6 million of deferred income on shipments to distributors. At December 31, 2015, the Company had $2.6 million of deferred revenue and $1.2 million of deferred cost of sales recognized as $1.4 million of deferred income on shipments to distributors.

Products returned by distributors and subsequently scrapped have historically been immaterial to the Company’s results of operations. The Company routinely evaluates the risk of impairment of the deferred cost of sales component of the deferred income on shipments to distributors account. Because of the historically immaterial amounts of inventory that have been scrapped, and historically rare instances where discounts given to a distributor result in a price less than our cost, the Company believes the deferred costs are recorded at their approximate carrying values.

For licenses of technology, recognition of revenue is dependent upon whether the Company delivered rights to the technology, and whether there are future performance obligations. In some instances, the license agreements call for future milestones to be met for amounts to be due from the customer. In such scenarios, revenue is recognized using the milestone method, whereby revenue is recognized upon the completion of substantive milestones once the customers acknowledge the milestones have been met and the collection of the amounts are reasonably assured. Royalties received are recognized when reported to the Company, which generally coincides with the receipt of payment.

Net Loss per Common Share

Basic net loss per common share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period, without consideration of potentially dilutive securities. Diluted net loss per common share is the same as basic net loss per common share since the effect of potentially dilutive securities is anti-dilutive.

Recent Accounting Pronouncements

In August 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-15, Statement of Cash Flows (Topic 230). This ASU provides guidance intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. ASU 2016-15 will become effective for the Company on January 1, 2018 and early adoption is permitted. The Company is currently evaluating the impact of this guidance on its financial statements.

Balance Sheet Components

9 Months Ended

Sep. 30, 2016

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

3. Balance Sheet Components

Inventory

Inventory consisted of the following (in thousands):


	September 30, 2016		December 31, 2015
Raw materials	$	1,114	$	361
Work-in-process		3,191		2,205
Finished goods		998		1,610

Total inventory	$	5,303	$	4,176

Intangible Assets, Net

In 2008, the Company spun-out of Freescale Semiconductor, Inc. (“Freescale,” a wholly-owned subsidiary of NXP Semiconductors N.V.) and acquired certain intellectual property assets and related licenses used in the MRAM business of Freescale. The value assigned to these acquired intangible assets was $910,000. Intangible assets, net consisted of the following (in thousands):


	September 30, 2016			December 31, 2015
Acquired technology	$	910		$	910
Less: accumulated amortization		(877	)		(778	)

Total intangible assets, net	$	33		$	132

Amortization expense was $33,000 and $30,000 for the three months ended September 30, 2016 and 2015, respectively, and $99,000 and $120,000 for the nine months ended September 30, 2016 and 2015, respectively. The carrying value of the intangible assets will be fully amortized by December 31, 2016.

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	September 30, 2016		December 31, 2015
Accrued deferred offering costs	$	1,155	$	—
Accrued payroll-related expenses		1,079		636
Accrued manufacturing-related costs		—		339
Deferred licensing revenue		250		250
Deferred rent		238		220
Accrued sales commissions payable to sales representatives		133		165
Other		259		145

Total accrued liabilities	$	3,114	$	1,755

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	4. Commitments and Contingencies *Operating Leases* In August 2016, the Company entered into an amendment to the facility lease for its design facility located in Austin, Texas to increase the leased space from 5,002 square feet to 11,084 square feet and extend the lease term from September 2016 to January 2022. The aggregate amount of payments due under the amended lease is $1.1 million.

Debt and Related Warrants

9 Months Ended

Sep. 30, 2016

Debt Disclosure [Abstract]

Debt and Related Warrants

5. Debt and Related Warrants

Warrants

In connection with a Loan and Security Agreement executed with Silicon Valley Bank in December 2010 (the “SVB Credit Facility”), the Company issued to Silicon Valley Bank a warrant to purchase 3,076 shares of the Company’s Series A redeemable convertible preferred stock at an exercise price of $26.00 per share. The warrant can be exercised at any time and expires on December 14, 2019. In the event of an IPO of the Company’s common stock, at which time the Series A redeemable convertible preferred stock would convert into common stock, the warrant will become exercisable for 3,076 shares of the Company’s common stock. The Company recorded the warrant as a debt discount of $63,000 and as a liability on the balance sheet at its fair value. The fair value of the warrant was $28,000 and $32,000 as of September 30, 2016 and December 31, 2015, respectively.

In connection with the Amended SVB Credit Facility, the Company issued to Silicon Valley Bank a warrant to purchase 6,153 shares of the Company’s Series B redeemable convertible preferred stock at an exercise price of $26.00 per share. The warrant can be exercised at any time and expires 10 years after the date of issuance. In the event of an IPO of the Company’s common stock, at which time the Series B redeemable convertible preferred stock would convert into common stock, the warrant will become exercisable for 6,153 shares of the Company’s common stock. The Company recorded the warrant as a debt discount and as a liability on the balance sheet at its fair value of $106,000 on the date of issuance using the Black-Scholes option-pricing model. The fair value of the warrant was $92,000 and $98,000 at September 30, 2016 and December 31, 2015, respectively.

2015 Facility

In June 2015, the Company executed a Loan and Security Agreement with Ares Venture Finance (“2015 Credit Facility”) comprising an $8.0 million term loan and a $4.0 million revolving loan. The term loan provides for interest at a floating rate equal to the greater of (a) 8.75% or (b) LIBOR plus 7.75% and has a term of four years. The term loan is payable in 15 monthly installments of interest only and 33 payments of principal and interest with an end-of-term fee of $180,000 due upon maturity. The revolving loan provides for interest at a floating rate equal to the prime rate plus 3.75% and has a term of two years. The Company may draw upon the loan facility for working capital purposes as required depending upon accounts receivable balances and other required conditions. In January 2016, the Company borrowed $1.5 million from the revolving loan. A portion of the proceeds was used to pay off the outstanding balance on the Amended SVB 2014 Credit Facility.

Security for the 2015 Credit Facility includes all of the Company’s assets except for leased equipment. The 2015 Credit Facility contains customary covenants restricting the Company’s activities, including limitations on its ability to sell assets, engage in mergers and acquisitions, enter into transactions involving related parties, incur indebtedness or grant liens or negative pledges on its assets, make loans or make other investments. Under these covenants, the Company is prohibited from paying dividends with respect to its capital stock. The Company was in compliance with all covenants at September 30, 2016 and December 31, 2015.

In connection with the 2015 Credit Facility, the Company issued to Ares Venture Finance a warrant to purchase 18,461 shares of the Company’s Series B redeemable convertible preferred stock at an exercise price of $26.00 per share. The warrant can be exercised at any time and expires 10 years after the date of issuance. In the event of an IPO of the Company’s common stock at which time the Series B redeemable convertible preferred stock would convert into common stock, the warrant will become exercisable for 18,461 shares of the Company’s common stock. The Company recorded the warrant as a debt discount and as a liability on the balance sheet at its fair value of $307,000 on the date of issuance using the Black-Scholes option-pricing model with the following assumptions: no dividend yield, an estimated life equal to ten years, a risk-free interest rate of 2.41%, and volatility of 51.8%. The fair value of the warrant was $285,000 and $307,000 at September 30, 2016 and December 31, 2015, respectively.

The carrying value of the Company’s 2015 Credit Facility at September 30, 2016 was as follows (in thousands):


	Current Portion			Long-Term Debt			Total
Debt, including end of term fee	$	4,054		$	5,028		$	9,082
Less: discount attributable to warrants, end of term fee and debt issuance cost		(210	)		(114	)		(324	)

Net carrying value of debt	$	3,844		$	4,914		$	8,758

The carrying value of the Company’s 2015 Credit Facility at December 31, 2015 was as follows (in thousands):


	Current Portion		Long-Term Debt			Total
Debt, including end of term fee	$	970	$	7,210		$	8,180
Less: discount attributable to warrants, end of term fee and debt issuance cost		—		(471	)		(471	)

Net carrying value of debt	$	970	$	6,739		$	7,709

The table below shows the principal repayments of the 2015 Credit Facility as of September 30, 2016 (in thousands):


	Principal Repayment
2016 (remaining three months)	$	727
2017		4,054
2018		2,909
2019		1,392

Total principal repayments	$	9,082

Capital Lease Obligations

The Company leases certain equipment under capital lease obligations expiring at various dates in 2016. Future minimum lease payments of the capital lease obligations as of September 30, 2016, are $60,000.

Property and equipment under capital leases amounted to $463,000 and $431,000 at September 30, 2016 and December 31, 2015, respectively. Accumulated depreciation and amortization on these assets was $403,000 and $256,000 at September 30, 2016 and December 31, 2015, respectively.

Redeemable Convertible Preferred Stock and Stockholders' Deficit

9 Months Ended

Sep. 30, 2016

Equity [Abstract]

Redeemable Convertible Preferred Stock and Stockholders' Deficit

6. Redeemable Convertible Preferred Stock and Stockholders’ Deficit

In July 2016, the Company’s Board of Directors and stockholders approved the Certificate of Amendment of Amended and Restated Certificate of Incorporation to increase the authorized capital stock of the Company from 243,080,000 shares, consisting of 175,000,000 shares of common stock, par value $0.0001 and 68,080,000 shares of redeemable convertible preferred stock, par value $0.0001, to an authorized capital stock of 281,080,000 shares consisting of 204,000,000 shares of common stock and 77,080,000 shares of redeemable convertible preferred stock.

Redeemable Convertible Preferred Stock

The following table summarizes the authorized, issued and outstanding redeemable convertible preferred stock of the Company as of September 30, 2016 and December 31, 2015 (in thousands, except share amounts):


	Shares Authorized				Shares Issued and Outstanding		Carrying Value		Liquidation Preference
	September 30, 2016		December 31, 2015		Shares Issued and Outstanding		Carrying Value		Liquidation Preference
Series A		35,580,000		35,580,000		1,365,379	$	35,500	$	35,500
Series B		41,500,000		32,500,000		1,120,820		29,142		29,142

Total		77,080,000		68,080,000		2,486,199	$	64,642	$	64,642

Common Stock

Common stockholders are entitled to dividends if and when declared by the board of directors subject to the prior rights of the preferred stockholders. As of September 30, 2016, no dividends on common stock had been declared by the board of directors.

The Company had reserved shares of common stock for future issuance as follows:


	September 30, 2016		December 31, 2015
Redeemable convertible preferred stock		2,486,199		2,486,199
Options issued and outstanding		1,262,294		927,175
Shares available for future option grants		57,654		55,330
Redeemable convertible preferred stock warrants		27,690		27,690

Total		3,833,837		3,496,394

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.5-02(31))
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
-Subparagraph (SX 210.5-02(30))
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Stock-Based Compensation

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

7. Stock-Based Compensation

The following table summarizes the stock option activity:


				Options Outstanding
	Options Available for Grant			Number of Options			Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (years)		Aggregate Intrinsic Value
											(In thousands)
Balance—December 31, 2015		55,330			927,175		$	4.43		7.3	$	6,500
Options authorized		348,078			—			—
Options granted		(406,023	)		406,023			15.86
Options exercised		—			(10,635	)		4.43				75
Options cancelled/forfeited		60,269			(60,269	)		4.42

Balance—September 30, 2016		57,654			1,262,294		$	8.11		7.6	$	3,056

Options exercisable—December 31, 2015					590,847		$	4.42		6.4	$	4,148

Options vested and expected to vest—December 31, 2015					927,175		$	4.43		7.3	$	6,500

Options exercisable—September 30, 2016					680,667		$	4.73		6.2	$	2,368

Options vested and expected to vest—September 30, 2016					1,262,294		$	8.11		7.6	$	3,056

The aggregate intrinsic values of options outstanding, exercisable, vested and expected to vest were calculated as the difference between the exercise price of the options and the estimated fair value of the Company’s common stock, as determined by the board of directors, as of September 30, 2016 and December 31, 2015.

The total grant date fair value of options vested was $129,000 and $102,000 during the three months ended September 30, 2016 and 2015, respectively, and $415,000 and $271,000 for the nine months ended September 30, 2016 and 2015, respectively.

The weighted-average grant date fair value of employee options granted during the three months ended September 30, 2016 and 2015 were $3.86 and $6.24 per share, respectively, and during the nine months ended September 30, 2016 and 2015 were $3.86 and $4.28 per share, respectively.

2016 Employee Incentive Plan

The Company’s board of directors adopted the 2016 Equity Incentive Plan (the “2016 Plan”) on April 25, 2016, which was subsequently approved on September 20, 2016 by the Company’s stockholders. The 2016 Plan became effective on October 7, 2016, the date the Company’s registration statement was declared effective by the SEC. No further grants will be made under the Company’s 2008 Equity Incentive Plan (the “2008 Plan”). However, any outstanding stock awards granted under the 2008 Plan will remain outstanding, subject to the terms of the Company’s 2008 Plan and the applicable stock award agreements, until such outstanding stock awards that are stock options are exercised or until they terminate or expire by their terms, or until such stock awards are fully settled, terminated or forfeited.

The Company’s 2016 Plan provides for the grant of incentive stock options (“ISOs”), nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance-based stock awards, and other forms of equity compensation to employees, directors and consultants. In addition, the Company’s 2016 Plan provides for the grant of performance cash awards to employees, directors and consultants.

The maximum number of shares of common stock that may be issued under the Company’s 2016 Plan is 500,000. The number of shares of common stock reserved for issuance under the Company’s 2016 Plan will automatically increase on January 1 of each year, beginning on January 1, 2017, and continuing through and including January 1, 2024, by 3% of the total number of shares of capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s board of directors. The maximum number of shares that may be issued upon the exercise of ISOs under the Company’s 2016 Plan is 500,000.

2016 Employee Stock Purchase Plan

The Company’s board of directors adopted the 2016 Employee Stock Purchase Plan (the “ESPP”) on April 25, 2016, which was subsequently approved on September 20, 2016 by the Company’s stockholders. The purpose of the ESPP is to secure the services of new employees, to retain the services of existing employees and to provide incentives for such individuals to exert maximum efforts toward the Company’s success and that of the Company’s affiliates. The ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the Code. The board of directors, or a duly authorized committee thereof, will administer the Company’s ESPP.

The maximum aggregate number of shares of common stock that may be issued pursuant to the exercise of purchase rights under the Company’s ESPP that are granted to employees or to employees of any of the Company’s designated affiliates is 96,153 shares. Additionally, the number of shares of common stock reserved for issuance under the Company’s ESPP will increase automatically each year, beginning on January 1, 2017, and continuing through and including January 1, 2026, by 1% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or a lesser number as determined by the board of directors. Shares subject to purchase rights granted under the Company’s ESPP that terminate without having been exercised in full will not reduce the number of shares available for issuance under the Company’s ESPP.

Stock-based Compensation Expense

The Company recognized stock-based compensation expense as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Research and development	$	99	$	45	$	188	$	119
General and administrative		182		52		282		137
Sales and marketing		28		18		50		45

Total	$	309	$	115	$	520	$	301

As of September 30, 2016, there was $2.0 million of total unrecognized compensation expense related to unvested options which is expected to be recognized over a weighted-average period of 2.9 years.

Employee Stock-based Compensation

Stock-based compensation expense for employees was $279,000 and $110,000 for the three months ended September 30, 2016 and 2015, respectively, and $480,000 and $289,000 for the nine months ended September 30, 2016 and 2015, respectively.

The Company estimated the fair value of each option using the Black-Scholes option-pricing model. The fair value of employee stock options is being amortized on a straight-line basis over the requisite service period of the awards. The fair value of employee stock options was estimated using the assumptions below. Each of these inputs is subjective and its determination generally requires significant judgment.

Three Months Ended
September 30,

Nine Months Ended
September 30,

2016

2015

2016

2015

Expected volatility

44.4 – 45.1

44.1 – 45.6

44.4 – 45.1

44.1 – 48.7

Risk-free interest rate

1.12 – 1.36

1.71 – 1.78

1.12 – 1.36

1.51 – 1.79

Expected term (in years)

5.2 – 6.0

5.6 – 6.0

5.2 – 6.1

5.6 – 6.1

Dividend yield

—

Non-employee Stock-based Compensation

Stock-based compensation expense related to stock options granted to non-employees is recognized as the stock options vest. During the three and nine months ended September 30, 2016, the Company granted a total of 21,633 stock options to non-employees. No stock options were granted to non-employees during the three and nine months ended September 30, 2015.

As of September 30, 2016, options to purchase 32,324 shares of common stock were outstanding with a weighted-average exercise price of $12.08 per share.

Stock-based compensation expense for non-employees was $30,000 and $5,000 for the three months ended September 30, 2016 and 2015, respectively, and $40,000 and $12,000 for the nine months ended September 30, 2016 and 2015, respectively.

The Company believes that the fair value of the stock options is more reliably measurable than the fair value of services received.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2016
Related Party Transactions [Abstract]
Related Party Transactions	8. Related Party Transactions *Convertible Promissory Notes* In January 2016, the Company entered into a Note Purchase Agreement with several of its stockholders for the issuance of convertible promissory notes (the “2016 Notes”) for an aggregate amount of $5.0 million. The 2016 Notes bear interest at 5.0% per annum and have a maturity date of September 30, 2016. The outstanding principal amount and accrued interest on the 2016 Notes are convertible into shares of Series B redeemable convertible preferred stock, at any time, upon written election of the holders of at least a majority of the outstanding principal balance of the 2016 Notes. In the event of an equity financing with proceeds in excess of $5.0 million (“Qualified Financing”) prior to the maturity of the 2016 Notes, the outstanding principal and accrued interest convert into shares of stock issued in the equity financing based on a price per share equal to the price per share paid by investors in said financing. In the event of an IPO, the outstanding principal and accrued interest convert into shares of common stock at a price per share equal to 80% of the per share price of the common stock issued in the IPO. In the event of a deemed liquidation event occurring before the maturity date, the 2016 Notes will be repaid in cash in an amount equal to three times the outstanding principal amount. The redemption of the 2016 Notes upon a deemed liquidation event and in the event of an IPO are contingent redemption features that are not clearly and closely related to the debt instrument and thus have been bifurcated and recognized as a derivative liability on the balance sheet as of September 30, 2016. The compound derivative was recorded as a debt discount at fair value of $653,000 on the issuance date of the 2016 Notes and is being amortized over the term of the 2016 Notes using the effective interest method. At September 30, 2016, the carrying values of the 2016 Notes and the derivative liability were $5.1 million and $70,000, respectively. In August 2016, the Company entered into a Note Purchase Agreement with existing stockholders for the issuance of subordinated convertible promissory notes (the “2016 Bridge Notes”) for an aggregate principal amount of $3.5 million. The 2016 Bridge Notes bear interest at 5.0% per annum and have a maturity date of September 30, 2016. In the event of an equity financing with proceeds in excess of $5.0 million (“Qualified Financing”) prior to the maturity of the 2016 Bridge Notes, the outstanding principal and accrued interest convert into shares of stock issued in the Qualified Financing based on a price per share equal to the price per share paid by investors in such financing. In the event of an IPO, the outstanding principal and accrued interest convert into shares of common stock at a price per share equal to 80% of the per share price of the common stock issued in the IPO. In the event of a deemed liquidation event occurring before the maturity date, the 2016 Bridge Notes will be repaid in cash in an amount equal to three times the outstanding principal amount. The Company may not prepay the 2016 Bridge Notes without the consent of the Company and the majority holders of the outstanding balance of the promissory notes. The redemption of the 2016 Bridge Notes upon a deemed liquidation event and in the event of an IPO are contingent redemption features that are not clearly and closely related to the debt instrument and thus have been bifurcated and recognized as a derivative liability on the balance sheet as of September 30, 2016. The compound derivative was recorded as a debt discount at fair value of $264,000 on the issuance date of the 2016 Bridge Notes and is being amortized over the term of the 2016 Bridge Notes using the effective interest method. At September 30, 2016, the carrying values of the 2016 Bridge Notes and the derivative liability were $3.4 million and $50,000, respectively. In September 2016, the Company entered into an amendment to its January 2016 and August 2016 convertible promissory notes for $5.0 million and $3.5 million, respectively, to extend the maturity date of the notes from September 30, 2016 to December 15, 2016. *Joint Development Agreement—GLOBALFOUNDRIES* On October 17, 2014, the Company entered into a Joint Development Agreement (“JDA”) with GLOBALFOUNDRIES, Inc. (“GF”), a related party due to its equity ownership in the Company, for the joint development of the Company’s Spin Torque MRAM (“ST-MRAM”) technology. The term of the agreement is the later of four years from the effective date or until the completion, termination or expiration of the last statement of work entered into pursuant to the JDA. The JDA also states that the specific terms and conditions for the production and supply of the developed ST-MRAM technology would be pursuant to a separate manufacturing agreement entered into between the parties. Under the JDA, each party licenses its relevant intellectual property to the other party. For certain jointly developed works, the parties have agreed to follow an invention allocation procedure to determine ownership. In addition, GF possesses the exclusive right to manufacture the Company’s discrete and embedded ST-MRAM devices developed pursuant to the agreement until the earlier of three years after the qualification of the MRAM device for a particular technology node or four years after the completion of the relevant statement of work under which the device was developed. For the same exclusivity period associated with the relevant device, GF agreed not to license intellectual property developed in connection with the JDA to named competitors of the Company. Generally, unless otherwise specified in the agreement or a statement of work, the Company and GF share project costs, which do not include personnel or production qualification costs, equally under the JDA. If GF manufactures, sells or transfers to customers wafers containing production quantified ST-MRAM devices that utilize certain design information, GF will be required to pay the Company a royalty. The term of the agreement is four years and is extended until the completion of any development work, if later. In May 2016, the Company entered into an amendment to the JDA to modify the payment schedule and clarify its payment obligations for certain past project costs. Under the amendment, GF has the right to terminate the JDA if the Company does not pay the project costs, with interest, by an agreed-upon date in December 2016. As of September 30, 2016 and December 31, 2015, $6.2 million and $3.5 million, respectively, were payable to GF for the Company’s share of the project costs under the JDA. The Company incurred project costs, recognized as research and development expense, of $480,000 and $905,000 for the three months ended September 30, 2016 and 2015, respectively, and $2.4 million and $2.7 million during the nine months ended September 30, 2016 and 2015, respectively. On October 21, 2014, GF participated, along with other investors, in the Company’s Series B redeemable convertible preferred stock financing and purchased 192,307 shares at $26.00 per share. Contemporaneously, the Company sold 461,538 shares of its common stock to GF at a discounted price of $0.00026 per share. The common shares vest upon the achievement of a goal as set forth in the Statement of Work #1 (the “SOW”) under the JDA. The unvested common shares are subject to repurchase by the Company, if the JDA is terminated for any reason, for a one-year period after such termination, at a price that is the lower of the original price paid by GF or the fair value of the Company’s common stock as of the date of repurchase. The Company has determined that the issuance of these shares of common stock to GF represents compensation for services to be provided under the JDA. Accordingly, the shares are accounted for similar to a stock award granted to a non-employee of the Company and are remeasured to their fair value as they vest. Although the shares issued do not commence vesting until the achievement of the product qualification (the “Initial Measurement Date”), the Company has deemed it probable that the qualification requirement will be met and compensation expense related to the shares issued is being recognized prior to the Initial Measurement Date. Due to the vesting conditions, there will be multiple measurement dates, occurring on the Initial Measurement Date and at the end of each month thereafter. The fair value of vesting shares is effectively fixed at each measurement date while the fair value of the remaining unvested shares will be remeasured each subsequent measurement date until the shares are fully vested. During the three months ended September 30, 2016, GF achieved the product qualification as set forth under the SOW. As such, a total of 211,538 shares of common stock became vested on August 21, 2016, the designated Initial Measurement Date. Subsequent to the Initial Measurement Date through September 30, 2016, an additional 9,615 shares of common stock became vested. As of September 30, 2016, there were 240,385 shares unvested that were subject to repurchase. The Company recognized non-cash compensation expense of $(691,000) and $494,000 during the three months ended September 30, 2016 and 2015, respectively, and $751,000 and $1.0 million during the nine months ended September 30, 2016 and 2015, respectively, in research and development expense related to the vesting of the shares of common stock. The Company recognizes compensation expense based on the estimated fair value of the common stock at each reporting period, which was $8.00 and $13.52 per share as of September 30, 2016 and December 31, 2015, respectively. The decrease in the fair value of the common stock during the three months ended September 30, 2016 resulted in a reversal of compensation expense previously recognized on the unvested shares. *Transactions with Freescale* The Company has entered into various transactions with Freescale (a wholly-owned subsidiary of NXP), a related party due to its equity ownership in the Company. The Company leases its manufacturing facility in Chandler, Arizona, from Freescale and total rent payments made were $267,000 and $257,000 during the three months ended September 30, 2016 and 2015, respectively, and $787,000 and $839,000 during the nine months ended September 30, 2016 and 2015, respectively. Freescale also performs processing of the Company’s products in its facility which are capitalized as part of the cost of inventory. The total processing costs incurred by the Company were $702,000 and $722,000 for the three months ended September 30, 2016 and 2015, respectively, and $2.0 million and $2.6 million for the nine months ended September 30, 2016 and 2015, respectively. In addition, Freescale is one of the Company’s largest customers for the sale of embedded wafers, and total revenue from Freescale was $662,000 and $902,000 during the three months ended September 30, 2016 and 2015, respectively, and $1.4 million and $2.7 million for the nine months ended September 30, 2016 and 2015, respectively. Amounts due from Freescale were $619,000 and $564,000 at September 30, 2016, and December 31, 2015, respectively. Amounts due to Freescale were $551,000 and $207,000 at September 30, 2016, and December 31, 2015, respectively.

Net Loss Per Common Share

9 Months Ended

Sep. 30, 2016

Earnings Per Share [Abstract]

Net Loss Per Common Share

9. Net Loss Per Common Share

The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2016			2015			2016			2015
Numerator:
Net loss	$	(1,444	)	$	(4,509	)	$	(11,400	)	$	(11,930	)

Denominator:
Weighted-average common shares outstanding		3,023,794			3,013,723			3,019,238			3,013,723
Less: weighted-average unvested common shares subjected to repurchase		(366,220	)		(461,538	)		(429,534	)		(461,538	)

Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted		2,657,574			2,552,185			2,589,704			2,552,185

Net loss per common share, basic and diluted	$	(0.54	)	$	(1.77	)	$	(4.40	)	$	(4.67	)

The following outstanding shares of potentially dilutive securities have been excluded from diluted net loss per common share for the periods presented, because their inclusion would be anti-dilutive:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Redeemable convertible preferred stock on an as-converted basis		2,486,199		2,486,199		2,486,199		2,486,199
Options to purchase common stock		1,262,294		946,593		1,262,294		946,593
Common stock subject to repurchase		240,385		461,538		240,385		461,538
Redeemable convertible preferred stock warrants on an as-converted basis		27,690		27,690		27,690		27,690

Total		4,016,568		3,922,020		4,016,568		3,922,020

Subsequent Events

9 Months Ended

Sep. 30, 2016

Subsequent Events [Abstract]

Subsequent Events

10. Subsequent Events

Initial Public Offering

In connection with the IPO discussed in Note 1, the following events occurred:

•

An aggregate of 2,486,199 shares of the Company’s common stock were issued to the holders of the redeemable convertible preferred stock upon the conversion of all shares of redeemable convertible preferred stock into common stock immediately prior to the closing of the IPO.

•

The outstanding balance of the 2016 Notes and 2016 Bridge Notes including accrued interest was converted into 1,361,023 shares of common stock.

•

All of the outstanding redeemable convertible preferred stock warrants converted to warrants to purchase shares of common stock upon the closing of the IPO.

•

The Company raised $37.2 million, net of underwriting discounts and commissions, but before offering costs.

Concurrent Private Placement

Concurrent with the IPO, the Company issued 625,000 shares of its common stock in a private placement for net proceeds of $4.7 million, after deducting the placement agent fee.

GLOBALFOUNDRIES

In November 2016, the Company repaid $4.7 million of its payable to GLOBALFOUNDRIES.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2016

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation

Use of Estimates

Use of Estimates

Concentration of Credit Risk

Concentration of Credit Risk


	Revenue												Accounts Receivable, net
	Three Months Ended September 30,						Nine Months Ended September 30,						As of September 30,			As of December 31,
Customers	2016			2015			2016			2015			2016			2015
Customer A		22	%		27	%		23	%		26	%		16	%		28	%
Customer B		*			20	%		*			12	%		21	%		23	%
Customer C		11	%		12	%		11	%		14	%		*			*
Customer D		*			*			*			*			11	%		*

*	Less than 10%

Deferred Offering Costs

Deferred Offering Costs

Fair Value of Financial Instruments

Fair Value of Financial Instruments

Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date.


	September 30, 2016
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,017	$	—	$	—	$	2,017

Total assets measured at fair value	$	2,017	$	—	$	—	$	2,017

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	405	$	405
Derivative liability		—		—		120		120

Total liabilities measured at fair value	$	—	$	—	$	525	$	525


	December 31, 2015
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,354	$	—	$	—	$	2,354

Total assets measured at fair value	$	2,354	$	—	$	—	$	2,354

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	437	$	437

Total liabilities measured at fair value	$	—	$	—	$	437	$	437


Balance at December 31, 2015	$	437
Change in fair value recorded in other income (expense), net		(32	)

Balance at September 30, 2016	$	405

The key assumptions used in the Black-Scholes option-pricing model for the valuation of the redeemable convertible preferred stock warrants were:


Expected volatility		42.4 – 52.0	%
Risk-free interest rate		1.22 – 1.86	%
Expected term (in years)		4 – 9
Exercise price	$	26.00
Dividend yield		—	%

The following table sets forth a summary of the changes in the fair value of the derivative liability, a Level 3 financial liability, which is measured on a recurring basis (in thousands):


Balance at December 31, 2015	$	—
Issuance of derivative liability		918
Change in fair value recorded in other income (expense), net		(798	)

Balance at September 30, 2016	$	120

Redeemable Convertible Preferred Stock Warrant Liability

Redeemable Convertible Preferred Stock Warrant Liability

Derivative Liability

Derivative Liability

Revenue Recognition

Revenue Recognition

Net Loss per Common Share

Net Loss per Common Share

Recent Accounting Pronouncements

Recent Accounting Pronouncements

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2016

Schedule of Revenue and Accounts Receivable for Each Significant Customer

For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable, net are as follows:


	Revenue												Accounts Receivable, net
	Three Months Ended September 30,						Nine Months Ended September 30,						As of September 30,			As of December 31,
Customers	2016			2015			2016			2015			2016			2015
Customer A		22	%		27	%		23	%		26	%		16	%		28	%
Customer B		*			20	%		*			12	%		21	%		23	%
Customer C		11	%		12	%		11	%		14	%		*			*
Customer D		*			*			*			*			11	%		*

*	Less than 10%

Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis


	September 30, 2016
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,017	$	—	$	—	$	2,017

Total assets measured at fair value	$	2,017	$	—	$	—	$	2,017

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	405	$	405
Derivative liability		—		—		120		120

Total liabilities measured at fair value	$	—	$	—	$	525	$	525


	December 31, 2015
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	2,354	$	—	$	—	$	2,354

Total assets measured at fair value	$	2,354	$	—	$	—	$	2,354

Liabilities:
Redeemable convertible preferred stock warrant liability	$	—	$	—	$	437	$	437

Total liabilities measured at fair value	$	—	$	—	$	437	$	437

Schedule of Assumptions Used in Valuation of Redeemable Convertible Preferred Stock Warrants

The key assumptions used in the Black-Scholes option-pricing model for the valuation of the redeemable convertible preferred stock warrants were:


Expected volatility		42.4 – 52.0	%
Risk-free interest rate		1.22 – 1.86	%
Expected term (in years)		4 – 9
Exercise price	$	26.00
Dividend yield		—	%

Redeemable Convertible Preferred Stock Warrants [Member]

Schedule of Change in Fair Value of Liability


Balance at December 31, 2015	$	437
Change in fair value recorded in other income (expense), net		(32	)

Balance at September 30, 2016	$	405

Derivative Liability [Member]

Schedule of Change in Fair Value of Liability

The following table sets forth a summary of the changes in the fair value of the derivative liability, a Level 3 financial liability, which is measured on a recurring basis (in thousands):


Balance at December 31, 2015	$	—
Issuance of derivative liability		918
Change in fair value recorded in other income (expense), net		(798	)

Balance at September 30, 2016	$	120

Balance Sheet Components (Tables)

9 Months Ended

Sep. 30, 2016

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Inventory

Inventory consisted of the following (in thousands):


	September 30, 2016		December 31, 2015
Raw materials	$	1,114	$	361
Work-in-process		3,191		2,205
Finished goods		998		1,610

Total inventory	$	5,303	$	4,176

Schedule of Intangible Assets

Intangible assets, net consisted of the following (in thousands):


	September 30, 2016			December 31, 2015
Acquired technology	$	910		$	910
Less: accumulated amortization		(877	)		(778	)

Total intangible assets, net	$	33		$	132

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	September 30, 2016		December 31, 2015
Accrued deferred offering costs	$	1,155	$	—
Accrued payroll-related expenses		1,079		636
Accrued manufacturing-related costs		—		339
Deferred licensing revenue		250		250
Deferred rent		238		220
Accrued sales commissions payable to sales representatives		133		165
Other		259		145

Total accrued liabilities	$	3,114	$	1,755

Debt and Related Warrants (Tables)

9 Months Ended

Sep. 30, 2016

Debt Disclosure [Abstract]

Summary of 2015 Credit Facility

The carrying value of the Company’s 2015 Credit Facility at September 30, 2016 was as follows (in thousands):


	Current Portion			Long-Term Debt			Total
Debt, including end of term fee	$	4,054		$	5,028		$	9,082
Less: discount attributable to warrants, end of term fee and debt issuance cost		(210	)		(114	)		(324	)

Net carrying value of debt	$	3,844		$	4,914		$	8,758

The carrying value of the Company’s 2015 Credit Facility at December 31, 2015 was as follows (in thousands):


	Current Portion		Long-Term Debt			Total
Debt, including end of term fee	$	970	$	7,210		$	8,180
Less: discount attributable to warrants, end of term fee and debt issuance cost		—		(471	)		(471	)

Net carrying value of debt	$	970	$	6,739		$	7,709

Summary of Principal Repayments of 2015 Credit Facility

The table below shows the principal repayments of the 2015 Credit Facility as of September 30, 2016 (in thousands):


	Principal Repayment
2016 (remaining three months)	$	727
2017		4,054
2018		2,909
2019		1,392

Total principal repayments	$	9,082

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Tables)

9 Months Ended

Sep. 30, 2016

Equity [Abstract]

Schedule of Authorized, Issued and Outstanding Redeemable Convertible Preferred Stock


	Shares Authorized				Shares Issued and Outstanding		Carrying Value		Liquidation Preference
	September 30, 2016		December 31, 2015		Shares Issued and Outstanding		Carrying Value		Liquidation Preference
Series A		35,580,000		35,580,000		1,365,379	$	35,500	$	35,500
Series B		41,500,000		32,500,000		1,120,820		29,142		29,142

Total		77,080,000		68,080,000		2,486,199	$	64,642	$	64,642

Summary of Common Stock Reserved for Future Issuance

The Company had reserved shares of common stock for future issuance as follows:


	September 30, 2016		December 31, 2015
Redeemable convertible preferred stock		2,486,199		2,486,199
Options issued and outstanding		1,262,294		927,175
Shares available for future option grants		57,654		55,330
Redeemable convertible preferred stock warrants		27,690		27,690

Total		3,833,837		3,496,394

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

+ References

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+ Details

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Stock Option Activity

The following table summarizes the stock option activity:


				Options Outstanding
	Options Available for Grant			Number of Options			Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (years)		Aggregate Intrinsic Value
											(In thousands)
Balance—December 31, 2015		55,330			927,175		$	4.43		7.3	$	6,500
Options authorized		348,078			—			—
Options granted		(406,023	)		406,023			15.86
Options exercised		—			(10,635	)		4.43				75
Options cancelled/forfeited		60,269			(60,269	)		4.42

Balance—September 30, 2016		57,654			1,262,294		$	8.11		7.6	$	3,056

Options exercisable—December 31, 2015					590,847		$	4.42		6.4	$	4,148

Options vested and expected to vest—December 31, 2015					927,175		$	4.43		7.3	$	6,500

Options exercisable—September 30, 2016					680,667		$	4.73		6.2	$	2,368

Options vested and expected to vest—September 30, 2016					1,262,294		$	8.11		7.6	$	3,056

Summary of Stock-Based Compensation Expense

The Company recognized stock-based compensation expense as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Research and development	$	99	$	45	$	188	$	119
General and administrative		182		52		282		137
Sales and marketing		28		18		50		45

Total	$	309	$	115	$	520	$	301

Schedule of Fair Value of Employee Stock Options

The fair value of employee stock options was estimated using the assumptions below. Each of these inputs is subjective and its determination generally requires significant judgment.

Three Months Ended
September 30,

Nine Months Ended
September 30,

2016

2015

2016

2015

Expected volatility

44.4 – 45.1

44.1 – 45.6

44.4 – 45.1

44.1 – 48.7

Risk-free interest rate

1.12 – 1.36

1.71 – 1.78

1.12 – 1.36

1.51 – 1.79

Expected term (in years)

5.2 – 6.0

5.6 – 6.0

5.2 – 6.1

5.6 – 6.1

Dividend yield

—

Net Loss Per Common Share (Tables)

9 Months Ended

Sep. 30, 2016

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Loss Per Share

The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2016			2015			2016			2015
Numerator:
Net loss	$	(1,444	)	$	(4,509	)	$	(11,400	)	$	(11,930	)

Denominator:
Weighted-average common shares outstanding		3,023,794			3,013,723			3,019,238			3,013,723
Less: weighted-average unvested common shares subjected to repurchase		(366,220	)		(461,538	)		(429,534	)		(461,538	)

Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted		2,657,574			2,552,185			2,589,704			2,552,185

Net loss per common share, basic and diluted	$	(0.54	)	$	(1.77	)	$	(4.40	)	$	(4.67	)

Schedule of Potentially Dilutive Securities Excluded from Diluted Net Loss Per Common Share


	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Redeemable convertible preferred stock on an as-converted basis		2,486,199		2,486,199		2,486,199		2,486,199
Options to purchase common stock		1,262,294		946,593		1,262,294		946,593
Common stock subject to repurchase		240,385		461,538		240,385		461,538
Redeemable convertible preferred stock warrants on an as-converted basis		27,690		27,690		27,690		27,690

Total		4,016,568		3,922,020		4,016,568		3,922,020

Organization and Nature of Business - Additional Information (Detail) $ / shares in Units, $ in Millions		1 Months Ended	9 Months Ended
	Oct. 07, 2016 USD ($) $ / shares shares	Sep. 30, 2016	Sep. 30, 2016
Organization And Nature Of Business [Line Items]
Date of entity incorporation			May 16, 2008
Reverse stock split ratio		0.038
Reverse stock split, description			In September 2016, the Company effected a 1-for-26 reverse stock split of all outstanding shares of the Company’s capital stock, including common stock and redeemable convertible preferred stock. All share, option, convertible promissory notes, warrant, and per share information presented in the condensed financial statements has been adjusted to reflect the stock split on a retroactive basis for all periods presented and all share information is rounded down to the nearest whole share after reflecting the stock split.
Subsequent Event [Member]
Organization And Nature Of Business [Line Items]
Net proceeds from issuance of common stock in private placement \| $	$ 4.7
IPO [Member] \| Subsequent Event [Member]
Organization And Nature Of Business [Line Items]
Stock issued during the period \| shares	5,000,000
Initial public offering price per share \| $ / shares	$ 8.00
Net proceeds from initial public offering \| $	$ 37.2
Private Placement [Member] \| Subsequent Event [Member]
Organization And Nature Of Business [Line Items]
Stock issued during the period \| shares	625,000

Summary of Significant Accounting Policies - Schedule of Revenue and Accounts Receivable for Each Significant Customer (Detail) - Customer Concentration Risk [Member]			3 Months Ended		9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue [Member] \| Customer A [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage			22.00%	27.00%	23.00%	26.00%
Revenue [Member] \| Customer B [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage				20.00%		12.00%
Revenue [Member] \| Customer C [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage			11.00%	12.00%	11.00%	14.00%
Accounts Receivable, net [Member] \| Customer A [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	16.00%	28.00%
Accounts Receivable, net [Member] \| Customer B [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	21.00%	23.00%
Accounts Receivable, net [Member] \| Customer D [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	11.00%

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Concentration Risk [Line Items]
Deferred offering cost	$ 3,101,000	$ 0
Deferred revenue	2,700,000	1,100,000
Deferred cost of sales	1,300,000	1,200,000
Deferred income on shipments to distributors	1,646,000	$ 1,440,000
Derivative Liability [Member]
Concentration Risk [Line Items]
Fair value inputs, future outcomes, minimum equity financing proceeds	$ 5,000,000

- Definition

Total carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue or other forms of income in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
-Subparagraph (SAB Topic 13.A.3(c).Q3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

+ Details

- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

+ References + Details

Summary of Significant Accounting Policies - Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 2,017	$ 2,354
Redeemable convertible preferred stock warrant liability	405	437
Derivative liability	120
Total liabilities measured at fair value	525	437
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	2,017	2,354
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Redeemable convertible preferred stock warrant liability	405	437
Derivative liability	120
Total liabilities measured at fair value	525	437
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	2,017	2,354
Money Market Funds [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 2,017	$ 2,354

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References + Details

Summary of Significant Accounting Policies - Schedule of Change in Fair Value of Liability (Detail) - Level 3 [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($)
Redeemable Convertible Preferred Stock Warrants [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2015	$ 437
Change in fair value recorded in other income (expense), net	(32)
Balance at September 30, 2016	405
Derivative Liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Issuance of redeemable convertible preferred stock warrants / derivative liability	918
Change in fair value recorded in other income (expense), net	(798)
Balance at September 30, 2016	$ 120

Summary of Significant Accounting Policies - Schedule of Assumptions Used in Valuation of Redeemable Convertible Preferred Stock Warrants (Detail) - Redeemable Convertible Preferred Stock Warrants [Member]	9 Months Ended
	Sep. 30, 2016 $ / shares
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Exercise price	$ 26
Dividend yield	0.00%
Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected volatility	42.40%
Risk-free interest rate	1.22%
Expected term (in years)	4 years
Dividend yield	0.00%
Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected volatility	52.00%
Risk-free interest rate	1.86%
Expected term (in years)	9 years
Dividend yield	0.00%

Balance Sheet Components - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Inventory, Net, Items Net of Reserve Alternative [Abstract]
Raw materials	$ 1,114	$ 361
Work-in-process	3,191	2,205
Finished goods	998	1,610
Total inventory	$ 5,303	$ 4,176

Balance Sheet Components - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2008
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Acquired intangible assets					$ 910,000
Amortization of intangible assets	$ 33,000	$ 30,000	$ 99,000	$ 120,000

Balance Sheet Components - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Acquired technology	$ 910	$ 910
Less: accumulated amortization	(877)	(778)
Total intangible assets, net	$ 33	$ 132

Balance Sheet Components - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued deferred offering costs	$ 1,155
Accrued payroll-related expenses	1,079	$ 636
Accrued manufacturing-related costs		339
Deferred licensing revenue	250	250
Deferred rent	238	220
Accrued sales commissions payable to sales representatives	133	165
Other	259	145
Total accrued liabilities	$ 3,114	$ 1,755

Commitments and Contingencies - Additional Information (Detail) $ in Millions		1 Months Ended
	Jul. 31, 2016 ft²	Aug. 31, 2016 USD ($) ft²
Commitments and Contingencies Disclosure [Abstract]
Area of operating lease \| ft²	5,002	11,084
Operating leases term of expiration	2016-09	2022-01
Aggregate amount of payments due under the amended lease \| $		$ 1.1

Debt and Related Warrants - Warrants - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2010
Class of Warrant or Right [Line Items]
Redeemable convertible preferred stock warrant liability	$ 405,000		$ 437,000
Warrants to Purchase Series A Redeemable Convertible Preferred Stock [Member] \| SVB Credit Facility [Member]
Class of Warrant or Right [Line Items]
Warrants issued				3,076
Warrant exercise price				$ 26.00
Warrant exercise expiration date	Dec. 14, 2019
Debt discount				$ 63,000
Redeemable convertible preferred stock warrant liability	$ 28,000		32,000
Warrants to Purchase Series B Redeemable Convertible Preferred Stock [Member] \| Amended SVB Credit Facility [Member]
Class of Warrant or Right [Line Items]
Warrants issued		6,153
Warrant exercise price		$ 26.00
Redeemable convertible preferred stock warrant liability	$ 92,000	$ 106,000	$ 98,000
Warrant exercise expiration period		10 years

Debt and Related Warrants - 2015 Facility - Additional Information (Detail)	1 Months Ended		9 Months Ended
	Jan. 31, 2016 USD ($)	Jun. 30, 2015 USD ($) Installment Payments $ / shares shares	Sep. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Redeemable convertible preferred stock warrant liability			$ 405,000	$ 437,000
2015 Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, covenant description			The 2015 Credit Facility contains customary covenants restricting the Company's activities, including limitations on its ability to sell assets, engage in mergers and acquisitions, enter into transactions involving related parties, incur indebtedness or grant liens or negative pledges on its assets, make loans or make other investments. Under these covenants, the Company is prohibited from paying dividends with respect to its capital stock.
Debt instrument, covenant compliance			The Company was in compliance with all covenants at September 30, 2016 and December 31, 2015.
2015 Credit Facility [Member] \| Warrants to Purchase Series B Redeemable Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Warrants issued \| shares		18,461
Warrant exercise price \| $ / shares		$ 26.00
Warrant exercise expiration period		10 years
Redeemable convertible preferred stock warrant liability		$ 307,000	$ 285,000	$ 307,000
Dividend yield		0.00%
Estimated life		10 years
Risk-free interest rate		2.41%
Volatility rate		51.80%
2015 Credit Facility [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Loan agreement amount		$ 8,000,000
Line of credit facility expiration period		4 years
Number of term loan installments \| Installment		15
Number of interest and principal Payments \| Payments		33
Term loan end-of-term fee		$ 180,000
2015 Credit Facility [Member] \| Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest rate, basis spread percentage		7.75%
2015 Credit Facility [Member] \| Term Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate		8.75%
2015 Credit Facility [Member] \| Revolving Loan [Member]
Debt Instrument [Line Items]
Loan agreement amount		$ 4,000,000
Line of credit facility expiration period		2 years
Proceeds from revolving loan	$ 1,500,000
2015 Credit Facility [Member] \| Revolving Loan [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Interest rate, basis spread percentage		3.75%

Debt and Related Warrants - Summary of 2015 Credit Facility (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Net carrying value of debt, Current Portion	$ 3,904	$ 1,175
Net carrying value of debt, Long-term debt	4,914	6,739
2015 Credit Facility [Member]
Line of Credit Facility [Line Items]
Debt, including end of term fee, Current Portion	4,054	970
Less: discount attributable to warrants, end of term fee and debt issuance cost, Current Portion	(210)
Net carrying value of debt, Current Portion	3,844	970
Debt, including end of term fee, Long-term debt	5,028	7,210
Less: discount attributable to warrants, end of term fee and debt issuance cost, Long-term debt	(114)	(471)
Net carrying value of debt, Long-term debt	4,914	6,739
Debt, including end of term fee, Total	9,082	8,180
Less: discount attributable to warrants, end of term fee and debt issuance cost, Total	(324)	(471)
Net carrying value of debt, Total	$ 8,758	$ 7,709

Debt and Related Warrants - Summary of Principal Repayments of 2015 Credit Facility (Detail) - 2015 Credit Facility [Member] - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
2016 (remaining three months)	$ 727
2017	4,054
2018	2,909
2019	1,392
Total principal repayments	$ 9,082	$ 8,180

Debt and Related Warrants - Capital Lease Obligations (Detail) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
Capital lease obligations future minimum lease payments	$ 60,000
Property and equipment under capital leases	463,000	$ 431,000
Capital lease obligations accumulated depreciation and amortization	$ 403,000	$ 256,000

Redeemable Convertible Preferred Stock and Stockholders' Deficit - Additional Information (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2016	Jul. 01, 2016	Jun. 30, 2016	Dec. 31, 2015
Equity [Abstract]
Shares authorized		281,080,000	243,080,000
Common stock, shares authorized	204,000,000	204,000,000	175,000,000	175,000,000
Common stock, par value	$ 0.0001		$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized	77,080,000	77,080,000	68,080,000	68,080,000
Redeemable convertible preferred stock, par value	$ 0.0001		$ 0.0001	$ 0.0001
Dividends on common stock	$ 0

Redeemable Convertible Preferred Stock and Stockholders' Deficit - Schedule of Authorized, Issued and Outstanding Redeemable Convertible Preferred Stock (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Jul. 01, 2016	Jun. 30, 2016	Dec. 31, 2015
Temporary Equity [Line Items]
Shares Authorized	77,080,000	77,080,000	68,080,000	68,080,000
Shares Issued and Outstanding	2,486,199			2,486,199
Carrying Value	$ 64,642			$ 64,642
Liquidation Preference	$ 64,642			$ 64,642
Series A Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Shares Authorized	35,580,000			35,580,000
Shares Issued and Outstanding	1,365,379			1,365,379
Carrying Value	$ 35,500			$ 35,500
Liquidation Preference	$ 35,500			$ 35,500
Series B Redeemable Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Shares Authorized	41,500,000			32,500,000
Shares Issued and Outstanding	1,120,820			1,120,820
Carrying Value	$ 29,142			$ 29,142
Liquidation Preference	$ 29,142			$ 29,142

Redeemable Convertible Preferred Stock and Stockholders' Deficit - Summary of Common Stock Reserved for Future Issuance (Detail) - shares	Sep. 30, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Reserved shares of common stock for future issuance	3,833,837	3,496,394
Redeemable Convertible Preferred Stock Warrants [Member]
Class of Stock [Line Items]
Reserved shares of common stock for future issuance	27,690	27,690
Options Issued and Outstanding [Member]
Class of Stock [Line Items]
Reserved shares of common stock for future issuance	1,262,294	927,175
Shares Available for Future Option Grants [Member]
Class of Stock [Line Items]
Reserved shares of common stock for future issuance	57,654	55,330
Redeemable Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Reserved shares of common stock for future issuance	2,486,199	2,486,199

Stock-Based Compensation - Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options Available for Grant, Outstanding, Beginning balance	55,330
Options Available for Grant, Options authorized	348,078
Options Available for Grant, Options granted	(406,023)
Options Available for Grant, Options exercised	0
Options Available for Grant, Options cancelled/forfeited	60,269
Options Available for Grant, Outstanding, Ending balance	57,654	55,330
Number of Options, Outstanding, Beginning balance	927,175
Number of Options, Options authorized	0
Number of Options, Options granted	406,023
Number of Options, Options exercised	(10,635)
Number of Options, Options cancelled/forfeited	(60,269)
Number of Options, Outstanding, Ending balance	1,262,294	927,175
Number of Options, exercisable	680,667	590,847
Number of Options, vested and expected to vest	1,262,294	927,175
Weighted - Average Exercise Price Per Share, Options outstanding, Beginning balance \| $ / shares	$ 4.43
Weighted - Average Exercise Price Per Share, Options authorized \| $ / shares	0
Weighted - Average Exercise Price Per Share, Options granted \| $ / shares	15.86
Weighted - Average Exercise Price Per Share, Options exercised \| $ / shares	4.43
Weighted - Average Exercise Price Per Share, Options cancelled/forfeited \| $ / shares	4.42
Weighted - Average Exercise Price Per Share, Options outstanding, Ending balance \| $ / shares	8.11	$ 4.43
Weighted - Average Exercise Price Per Share, Options exercisable \| $ / shares	4.73	4.42
Weighted - Average Exercise Price Per Share, Options vested and expected to vest \| $ / shares	$ 8.11	$ 4.43
Weighted - Average Remaining Contractual Life, Options outstanding	7 years 7 months 6 days	7 years 3 months 18 days
Weighted - Average Remaining Contractual Life, Options exercisable	6 years 2 months 12 days	6 years 4 months 24 days
Weighted - Average Remaining Contractual Life, Options vested and expected to vest	7 years 7 months 6 days	7 years 3 months 18 days
Aggregate Intrinsic Value, Options outstanding \| $	$ 3,056	$ 6,500
Aggregate Intrinsic Value, Options granted \| $	0	0
Aggregate Intrinsic Value, Options exercised \| $	75
Aggregate Intrinsic Value, Options cancelled/forfeited \| $	0	0
Aggregate Intrinsic Value, Options exercisable \| $	2,368	4,148
Aggregate Intrinsic Value, Options vested and expected to vest \| $	$ 3,056	$ 6,500

Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total grant date fair value of options vested	$ 129,000	$ 102,000	$ 415,000	$ 271,000
Number of stock options granted			406,023
Total unrecognized compensation expense related to unvested options	2,000,000		$ 2,000,000
Unrecognized compensation expense, weighted-average period expected to be recognized			2 years 10 months 24 days
Stock-based compensation expense	$ 309,000	115,000	$ 520,000	301,000
Non-employee stock-based compensation, number of options outstanding	1,262,294		1,262,294		927,175
Non-employee stock-based compensation, weighted-average exercise price	$ 8.11		$ 8.11		$ 4.43
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 279,000	$ 110,000	$ 480,000	$ 289,000
Non-Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted	21,633	0	21,633	0
Stock-based compensation expense	$ 30,000	$ 5,000	$ 40,000	$ 12,000
Non-employee stock-based compensation, number of options outstanding	32,324		32,324
Non-employee stock-based compensation, weighted-average exercise price	$ 12.08		$ 12.08
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value of employee options granted	$ 3.86	$ 6.24	$ 3.86	$ 4.28
2016 Employee Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock shares may be issued under the plan	500,000		500,000
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock			3.00%
2016 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock shares may be issued under the plan	96,153		96,153
Annual increases in the number of shares available for issuance, percentage of outstanding capital stock			1.00%
2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted			0

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 309	$ 115	$ 520	$ 301
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	99	45	188	119
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	182	52	282	137
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 28	$ 18	$ 50	$ 45

Stock-Based Compensation - Schedule of Fair Value of Employee Stock Options (Detail) - Options to Purchase Common Stock [Member]	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, Minimum	44.40%	44.10%	44.40%	44.10%
Expected volatility, Maximum	45.10%	45.60%	45.10%	48.70%
Risk-free interest rate, Minimum	1.12%	1.71%	1.12%	1.51%
Risk-free interest rate, Maximum	1.36%	1.78%	1.36%	1.79%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 2 months 12 days	5 years 7 months 6 days	5 years 2 months 12 days	5 years 7 months 6 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years	6 years	6 years 1 month 6 days	6 years 1 month 6 days

Related Party Transactions - Additional Information (Detail) - USD ($)			1 Months Ended			3 Months Ended		9 Months Ended
	Oct. 21, 2014	Oct. 17, 2014	Sep. 30, 2016	Aug. 31, 2016	Jan. 31, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Aug. 21, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Research and development expense						$ 3,111,000	$ 5,081,000	$ 14,342,000	$ 14,723,000
Estimated fair value of common stock per share			$ 8.00			$ 8.00		$ 8.00			$ 13.52
Related party sales						$ 662,000	902,000	$ 1,396,000	2,739,000
Due from related party			$ 619,000			$ 619,000		$ 619,000			$ 564,000
Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares of common stock, vested			9,615
Number of shares of common stock, unvested			240,385			240,385		240,385		211,538
Global Foundries, Inc. [Member] \| Common Stock [Member]
Related Party Transaction [Line Items]
Number of shares sold	461,538
Shares sold, price per share	$ 0.00026
Global Foundries, Inc. [Member] \| Research and Development [Member]
Related Party Transaction [Line Items]
Non-cash compensation expense (income)						$ (691,000)	494,000	$ 751,000	1,000,000
Global Foundries, Inc. [Member] \| Series B Redeemable Convertible Preferred Stock [Member]
Related Party Transaction [Line Items]
Number of shares sold	192,307
Shares sold, price per share	$ 26.00
Freescale [Member]
Related Party Transaction [Line Items]
Due to related party			$ 551,000			551,000		551,000			207,000
Rent paid						267,000	257,000	787,000	839,000
Processing cost						702,000	722,000	2,000,000	2,600,000
Related party sales						662,000	902,000	1,400,000	2,700,000
Due from related party			619,000			619,000		$ 619,000			564,000
2016 Convertible Promissory Notes [Member]
Related Party Transaction [Line Items]
Debt instrument, aggregate amount					$ 5,000,000
Debt instrument, interest rate					5.00%
Debt instrument, maturity date					Sep. 30, 2016			Dec. 15, 2016
Debt instrument, convertible, equity issuance trigger					$ 5,000,000
Debt instrument, threshold percentage					80.00%
Debt instrument, unamortized discount					$ 653,000
Debt instrument, carrying value			5,100,000			5,100,000		$ 5,100,000
Derivative liability			70,000			70,000		$ 70,000
2016 Bridge Notes [Member]
Related Party Transaction [Line Items]
Debt instrument, aggregate amount				$ 3,500,000
Debt instrument, interest rate				5.00%
Debt instrument, maturity date				Sep. 30, 2016				Dec. 15, 2016
Debt instrument, convertible, equity issuance trigger				$ 5,000,000
Debt instrument, threshold percentage				80.00%
Debt instrument, unamortized discount				$ 264,000
Debt instrument, carrying value			3,400,000			3,400,000		$ 3,400,000
Derivative liability			50,000			50,000		50,000
Joint Development Agreement [Member] \| Global Foundries, Inc. [Member]
Related Party Transaction [Line Items]
Agreement term		4 years
Due to related party			$ 6,200,000			6,200,000		6,200,000			$ 3,500,000
Research and development expense						$ 480,000	$ 905,000	$ 2,400,000	$ 2,700,000

Net Loss Per Common Share - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Numerator:
Net loss	$ (1,444)	$ (4,509)	$ (11,400)	$ (11,930)
Denominator:
Weighted-average common shares outstanding	3,023,794	3,013,723	3,019,238	3,013,723
Less: weighted-average unvested common shares subjected to repurchase	(366,220)	(461,538)	(429,534)	(461,538)
Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted	2,657,574	2,552,185	2,589,704	2,552,185
Net loss per common share, basic and diluted	$ (0.54)	$ (1.77)	$ (4.40)	$ (4.67)

Net Loss Per Common Share - Schedule of Potentially Dilutive Securities Excluded from Diluted Net Loss Per Common Share (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted net loss per common share	4,016,568	3,922,020	4,016,568	3,922,020
Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted net loss per common share	2,486,199	2,486,199	2,486,199	2,486,199
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted net loss per common share	1,262,294	946,593	1,262,294	946,593
Common Stock Subject to Repurchase [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted net loss per common share	240,385	461,538	240,385	461,538
Redeemable Convertible Preferred Stock Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted net loss per common share	27,690	27,690	27,690	27,690

Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - USD ($) $ in Millions		1 Months Ended
	Oct. 07, 2016	Nov. 18, 2016
Subsequent Event [Line Items]
Net proceeds from issuance of common stock in private placement	$ 4.7
Private Placement [Member]
Subsequent Event [Line Items]
Stock issued during period	625,000
IPO [Member]
Subsequent Event [Line Items]
Net proceeds from initial public offering	$ 37.2
Stock issued during period	5,000,000
Global Foundries, Inc. [Member]
Subsequent Event [Line Items]
Repayment of payables		$ 4.7
2016 Notes and 2016 Bridge Notes Member [Member]
Subsequent Event [Line Items]
Conversion of convertible securities	1,361,023
Redeemable Convertible Preferred Stock [Member]
Subsequent Event [Line Items]
Conversion of convertible securities	2,486,199