Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2020	Nov. 05, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Trading Symbol	ASPN
Entity Registrant Name	ASPEN AEROGELS, INC.
Entity Central Index Key	0001145986
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		26,867,920
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-36481
Entity Tax Identification Number	04-3559972
Entity Address, Address Line One	30 Forbes Road
Entity Address, Address Line Two	Building B
Entity Address, State or Province	MA
Entity Address, City or Town	Northborough
Entity Address, Postal Zip Code	01532
City Area Code	508
Local Phone Number	691-1111
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.00001 per share
Security Exchange Name	NYSE
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 11,314	$ 3,633
Accounts receivable, net of allowances of $295 and $144	20,072	32,254
Inventories	9,427	8,768
Prepaid expenses and other current assets	1,595	1,114
Total current assets	42,408	45,769
Property, plant and equipment, net	48,099	53,617
Operating lease right-of-use assets	3,702	4,032
Other long-term assets	88	84
Total assets	94,297	103,502
Current liabilities:
Accounts payable	8,354	12,596
Accrued expenses	4,081	8,057
Current portion of long-term debt	367
Revolving line of credit		3,123
Deferred revenue	2,275	5,620
Operating lease liabilities	1,056	1,038
Total current liabilities	16,133	30,434
Prepayment liability	9,568	9,786
Long-term debt	3,298
Operating lease liabilities long-term	3,845	4,292
Other long-term liabilities	566
Total liabilities	33,410	44,512
Commitments and contingencies (Note 8)
Stockholders’ equity:
Preferred stock, $0.00001 par value; 5,000,000 shares authorized, no shares issued and outstanding at September 30, 2020 and December 31, 2019
Common stock, $0.00001 par value; 125,000,000 shares authorized, 26,865,309 and 24,302,504 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively		0
Additional paid-in capital	562,657	545,140
Accumulated deficit	(501,770)	(486,150)
Total stockholders’ equity	60,887	58,990
Total liabilities and stockholders’ equity	$ 94,297	$ 103,502

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Allowance for accounts receivables	$ 295	$ 144
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	26,865,309	24,302,504
Common stock, shares outstanding	26,865,309	24,302,504

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 24,195	$ 35,425	$ 77,255	$ 92,870
Cost of revenue:
Gross profit	1,900	7,742	10,731	14,974
Operating expenses:
Research and development	2,088	2,046	6,436	5,842
Sales and marketing	2,755	3,992	9,051	11,012
General and administrative	3,761	3,857	10,682	11,449
Total operating expenses	8,604	9,895	26,169	28,303
Loss from operations	(6,704)	(2,153)	(15,438)	(13,329)
Interest expense, net	(49)	(136)	(182)	(280)
Total interest expense, net	(49)	(136)	(182)	(280)
Net loss	$ (6,753)	$ (2,289)	$ (15,620)	$ (13,609)
Net loss per share:
Basic and diluted	$ (0.25)	$ (0.09)	$ (0.60)	$ (0.57)
Weighted-average common shares outstanding:
Basic and diluted	26,728,205	24,171,811	26,150,236	24,074,565
Product [Member]
Revenue:
Total revenue	$ 23,939	$ 35,046	$ 76,772	$ 90,739
Cost of revenue:
Cost of revenue	22,243	27,510	66,403	76,703
Research Services [Member]
Revenue:
Total revenue	256	379	483	2,131
Cost of revenue:
Cost of revenue	$ 52	$ 173	$ 121	$ 1,193

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock 0.00001 Par Value [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2018	$ 70,254		$ 541,839	$ (471,585)
Beginning balance, shares at Dec. 31, 2018		23,973,517
Net loss	(6,002)			(6,002)
Stock compensation expense	878		878
Vesting of restricted stock units	(454)		(454)
Vesting of restricted stock units, shares		273,290
Ending balance at Mar. 31, 2019	64,676		542,263	(477,587)
Ending balance, shares at Mar. 31, 2019		24,246,807
Beginning balance at Dec. 31, 2018	70,254		541,839	(471,585)
Beginning balance, shares at Dec. 31, 2018		23,973,517
Net loss	(13,609)
Ending balance at Sep. 30, 2019	59,066		544,260	(485,194)
Ending balance, shares at Sep. 30, 2019		24,300,264
Beginning balance at Mar. 31, 2019	64,676		542,263	(477,587)
Beginning balance, shares at Mar. 31, 2019		24,246,807
Net loss	(5,318)			(5,318)
Stock compensation expense	996		996
Issuance of restricted stock, shares		50,328
Vesting of restricted stock units	10		10
Vesting of restricted stock units, shares		3,129
Ending balance at Jun. 30, 2019	60,344		543,249	(482,905)
Ending balance, shares at Jun. 30, 2019		24,300,264
Net loss	(2,289)			(2,289)
Stock compensation expense	1,011		1,011
Ending balance at Sep. 30, 2019	59,066		544,260	(485,194)
Ending balance, shares at Sep. 30, 2019		24,300,264
Beginning balance at Dec. 31, 2019	58,990		545,140	(486,150)
Beginning balance, shares at Dec. 31, 2019		24,302,504
Net loss	(3,169)			(3,169)
Stock compensation expense	992		992
Vesting of restricted stock units	(1,195)		(1,195)
Vesting of restricted stock units, shares		336,951
Proceeds from underwritten public offering, net of underwriting discounts and commissions of $1,093 and issuance costs of $285	14,751		14,751
Proceeds from underwritten public offering, net of underwriting discounts and commissions, shares		1,955,000
Ending balance at Mar. 31, 2020	70,369		559,688	(489,319)
Ending balance, shares at Mar. 31, 2020		26,594,455
Beginning balance at Dec. 31, 2019	58,990		545,140	(486,150)
Beginning balance, shares at Dec. 31, 2019		24,302,504
Net loss	(15,620)
Ending balance at Sep. 30, 2020	60,887		562,657	(501,770)
Ending balance, shares at Sep. 30, 2020		26,865,309
Beginning balance at Mar. 31, 2020	70,369		559,688	(489,319)
Beginning balance, shares at Mar. 31, 2020		26,594,455
Net loss	(5,698)			(5,698)
Stock compensation expense	1,007		1,007
Issuance of restricted stock, shares		45,066
Vesting of restricted stock units	16		16
Vesting of restricted stock units, shares		5,629
Proceeds from employee stock option exercises	869		869
Proceeds from employee stock option exercises, shares		200,159
Ending balance at Jun. 30, 2020	66,531		561,548	(495,017)
Ending balance, shares at Jun. 30, 2020		26,845,309
Net loss	(6,753)			(6,753)
Stock compensation expense	991		991
Proceeds from employee stock option exercises	118		118
Proceeds from employee stock option exercises, shares		20,000
Ending balance at Sep. 30, 2020	$ 60,887		$ 562,657	$ (501,770)
Ending balance, shares at Sep. 30, 2020		26,865,309

Consolidated Statements of Stockholders' Equity (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
Equity [Abstract]
Underwriting discounts and commissions	$ 1,093
Issuance costs	$ 285

Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
Consolidated Statements of Cash Flows - USD ($)	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net loss	$ (15,620,000)	$ (13,609,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	7,670,000	7,651,000
Amortization of debt issuance costs	6,000
Provision for bad debt	171,000	0
Stock-compensation expense	2,990,000	2,885,000
Reduction in the carrying amount of operating lease right-of-use assets	719,000	702,000
Changes in operating assets and liabilities:
Accounts receivable	12,011,000	1,203,000
Inventories	(659,000)	(6,141,000)
Prepaid expenses and other assets	(485,000)	(484,000)
Accounts payable	(3,794,000)	(2,865,000)
Accrued expenses	(3,976,000)	826,000
Deferred revenue	(3,563,000)	4,870,000
Operating lease liabilities	(818,000)	(743,000)
Other liabilities	566,000	(56,000)
Net cash used in operating activities	(4,782,000)	(5,761,000)
Cash flows from investing activities:
Capital expenditures	(2,600,000)	(1,589,000)
Net cash used in investing activities	(2,600,000)	(1,589,000)
Cash flows from financing activities:
Proceeds from underwritten public offering, net of underwriting discounts and commissions of $1,093	15,036,000
Issuance costs from underwritten public offering	(285,000)
Proceeds from issuance of long-term debt	3,686,000
Issuance costs from long-term debt	(27,000)
Proceeds from (repayments of) borrowings under line of credit, net	(3,123,000)	682,000
Prepayment proceeds under customer supply agreement		5,000,000
Proceeds from employee stock option exercises	987,000
Payments made for employee restricted stock tax withholdings	(1,211,000)	(464,000)
Net cash provided by financing activities	15,063,000	5,218,000
Net increase (decrease) in cash	7,681,000	(2,132,000)
Cash and cash equivalents at beginning of period	3,633,000	3,327,000
Cash and cash equivalents at end of period	11,314,000	1,195,000
Supplemental disclosures of cash flow information:
Interest paid	168,000	333,000
Income taxes paid	0	0
Supplemental disclosures of non-cash activities:
Initial recognition of operating lease liabilities related to right-of-use assets		5,995,000
Right-of-use assets obtained in exchange for new operating lease liabilities	389,000	353,000
Changes in accrued capital expenditures	$ (448,000)	$ (430,000)

Consolidated Statements of Cash Flows (Parenthetical) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($)
Statement Of Cash Flows [Abstract]
Underwriting discounts and commissions, net	$ 1,093

Description of Business and Basis of Presentation

9 Months Ended

Sep. 30, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Description of Business and Basis of Presentation

(1) Description of Business and Basis of Presentation

Nature of Business

Aspen Aerogels, Inc. (the Company) is an aerogel technology company that designs, develops and manufactures innovative, high-performance aerogel insulation used primarily in the energy infrastructure and building materials markets. In addition, the Company is developing high value applications for its aerogel technology in the electric vehicle market. The Company also conducts research related to aerogel technology supported by funding from several agencies of the U.S. government and other institutions in the form of research contracts. The Company has decided to cease efforts to secure additional funded research contracts and to wind down existing contract research activities.

The Company maintains its corporate offices in Northborough, Massachusetts. The Company has three wholly owned subsidiaries: Aspen Aerogels Rhode Island, LLC, Aspen Aerogels Germany, GmbH and Aspen Aerogels Georgia, LLC.

Liquidity

During the nine months ended September 30, 2020, the Company incurred a net loss of $15.6 million and used $4.8 million of cash in operations. On February 18, 2020, the Company received net proceeds of $14.8 million upon the completion of an underwritten public offering of the Company’s common stock. On May 4, 2020, Aspen Aerogels Rhode Island, LLC received loan proceeds of $3.7 million upon the execution of a promissory note pursuant to the Paycheck Protection Program (PPP) established by the Coronavirus Aid, Relief and Economic Security Act (CARES Act) and administered by the U.S. Small Business Administration (SBA) (see note 7). The Company had cash and cash equivalents of $11.3 million, total debt of $3.7 million and no outstanding borrowings under its revolving line of credit as of September 30, 2020 (see note 8). After giving effect to $1.4 million of outstanding letters of credit, the amount available to the Company at September 30, 2020 under the revolving line of credit was $8.1 million. The existing revolving line of credit matures on April 28, 2021.

The Company is increasing investment in the research and development of next-generation aerogel products and manufacturing process technologies. The Company is developing aerogel products and technologies for the electric vehicle market. The commercial potential for the Company’s technology in the electric vehicle market is significant and could require the Company to hire additional personnel, incur additional operating expenses, and incur capital expenditures to expand aerogel manufacturing capacity, build an automated fabrication operation, and meet automotive quality system requirements, among other items.

The Company expects its existing cash balance and the amount anticipated to be available under the existing revolving line of credit will be sufficient to support current operating requirements and research and development activities. However, the Company plans to supplement its cash balance and available credit with debt financings, customer prepayments, technology licensing fees or equity financings to provide the capital necessary to fund the evolving commercial opportunity in the electric vehicle market and other strategic business opportunities.

Unaudited Interim Financial Information

The accompanying unaudited interim consolidated financial statements include the accounts of the Company and have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Certain information and disclosures normally included in the consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the audited consolidated financial statements and accompanying notes in our Annual Report on Form 10-K for the year ended December 31, 2019 (the Annual Report), filed with the U.S. Securities and Exchange Commission on March 6, 2020.

In the opinion of the Company’s management, the unaudited interim consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and include all adjustments that are of a normal recurring nature and necessary for the fair statement of the Company’s financial position as of September 30, 2020 and the results of its operations and stockholders’ equity for the three and nine months ended September 30, 2020 and 2019 and the cash flows for the nine month periods then ended. The Company has evaluated subsequent events through the date of this filing.

The Company’s results of operations for the three and nine months ended September 30, 2020 are not necessarily indicative of the results to be expected for the year ending December 31, 2020 or any other period. In addition, the Company is uncertain of the ultimate duration and severity of the COVID-19 pandemic and recent global oil market volatility, and the impact they will have on the Company’s results of operations for the year ending December 31, 2020 or any other period.

Significant Accounting Policies

9 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Significant Accounting Policies

(2) Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements, which have been prepared in accordance with U.S. GAAP, include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of the consolidated financial statements requires the Company to make a number of estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include allowances for doubtful accounts, sales returns and allowances, product warranty costs, inventory valuation, the carrying amount of property and equipment, stock-based compensation and deferred income taxes. The Company evaluates its estimates and assumptions on an on-going basis using historical experience and other factors, including current economic conditions, which are believed to be reasonable under the circumstances. Management adjusts such estimates and assumptions when facts and circumstances warrant. Illiquid credit markets, volatile equity markets and declines in business investment can increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in these estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods.

Cash and Cash Equivalents

Cash equivalents include short-term, highly liquid instruments, which consist of money market accounts. All cash and cash equivalents are maintained with major financial institutions in North America. Deposits with these financial institutions may exceed the amount of insurance provided on such deposits; however, these deposits typically may be redeemed upon demand and, therefore, bear minimal risk.

Concentration of Credit Risk

Financial instruments, which potentially expose the Company to concentrations of credit risk, consist principally of accounts receivable. The Company maintains an allowance for doubtful accounts based on its assessment of the collectability of accounts receivable. The Company reviews the allowance for doubtful accounts quarterly. During the nine months ended September 30, 2020, the Company recorded a charge for estimated customer uncollectible accounts receivable of $0.2 million. The Company did not record a charge for uncollectible accounts receivable during the nine months ended September 30, 2019.

Revenue Recognition

The Company recognizes revenue in accordance with Accounting Standards Codification 606, Revenue from Contracts with Customers (ASC 606). See note 3 for further details.

Leases

On January 1, 2019, the Company adopted Accounting Standards Update (ASU) 2016-02, Leases (Topic 842). See note 9 for further details.

Stock-based Compensation

Stock-based compensation expense is measured at the grant date based on the fair value of the award. Expense is recognized on a straight-line basis over the requisite service period for all awards with service conditions. For performance-based awards, the grant date fair value is recognized as expense when the condition is probable of being achieved and then on a graded basis over the requisite service period. The Company uses the Black-Scholes option-pricing model to determine the fair value of service-based option awards, which requires a number of complex and subjective assumptions including fair value of the underlying security, the expected volatility

of the underlying security, a risk-free interest rate and the expected term of the option. The fair value of restricted stock and restricted stock unit grants is determined using the closing trading price of the Company’s common stock on the date of grant. The fair value of awards containing market conditions is determined using a Monte Carlo simulation model based upon the nature of the conditions, the expected volatility of the underlying security, and other relevant factors.

During the nine months ended September 30, 2020, the Company granted 165,430 restricted common stock units (RSUs) with a grant date fair value of $1.3 million and non-qualified stock options (NSOs) to purchase 617,627 shares of common stock with a grant date fair value of $2.4 million to employees under the 2014 Employee, Director, and Consultant Equity Incentive Plan (the 2014 Equity Plan). The RSUs and NSOs granted to employees will vest over a three-year period. During the nine months ended September 30, 2020, the Company also granted 45,066 shares of restricted common stock with a grant date fair value of $0.3 million and NSOs to purchase 58,902 shares of common stock with a grant date fair value of $0.2 million to its non-employee directors under the 2014 Equity Plan. The restricted common stock and NSOs granted to non-employee directors will vest upon the earlier of the date that is the one-year anniversary of the grant or the day prior to the Company’s annual meeting of stockholders to be held in 2021.

Stock-based compensation is included in cost of revenue or operating expenses, as applicable, and consists of the following:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Cost of product revenue	$	98	$	125	$	544	$	365
Research and development expenses		169		130		482		374
Sales and marketing expenses		179		168		524		461
General and administrative expenses		545		588		1,440		1,685
Total stock-based compensation	$	991	$	1,011	$	2,990	$	2,885

Pursuant to the “evergreen” provisions of the 2014 Equity Plan, the number of shares of common stock authorized for issuance under the plan automatically increased by 486,050 shares to 7,974,980 shares effective January 1, 2020.

As of September 30, 2020, 4,536,565 shares of common stock were reserved for issuance upon the exercise or vesting of outstanding stock-based awards granted under the 2014 Equity Plan. In addition, as of September 30, 2020, 81,663 shares of common stock were reserved for issuance upon the exercise of outstanding stock options granted under the Company’s 2001 Equity Incentive Plan, as amended (the 2001 Equity Plan). Any cancellations or forfeitures of the options outstanding under the 2001 Equity Plan will result in the shares reserved for issuance upon exercise of such options becoming available for grant under the 2014 Equity Plan. As of September 30, 2020, the Company has either reserved in connection with statutory tax withholdings or issued a total of 2,546,810 shares under the 2014 Equity Plan. As of September 30, 2020, there were 809,942 shares of common stock available for future grant under the 2014 Equity Plan.

Net Loss per Share

The Company calculates net loss per share of common stock based on the weighted-average number of shares of common stock outstanding during each period. Potential common stock equivalents are determined using the treasury stock method. The weighted-average number of shares of common stock included in the computation of diluted net loss gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and RSUs. Common equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive.

Segments

Operating segments are identified as components of an enterprise about which separate, discrete financial information is available for evaluation by the chief operating decision maker in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company’s chief operating decision maker reviews consolidated operating results to make decisions about allocating resources and assessing performance for the entire Company. The Company views its operations and manages its business as one operating segment.

Information about the Company’s total revenues, based on shipment destination or services location, is presented in the following table:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Revenue:
U.S.	$	9,736	$	15,191	$	31,501	$	41,415
International		14,459		20,234		45,754		51,455
Total	$	24,195	$	35,425	$	77,255	$	92,870

Warranty

The Company provides warranties for its products and records the estimated cost within cost of revenue in the period that the related revenue is recorded. The Company’s standard warranty period extends to one year from the date of shipment. This standard warranty provides that the Company’s products will be free from defects in material and workmanship, and will, under normal use, conform to the specifications for the product.

The Company’s products may be utilized in systems that involve new technical demands and new configurations. Accordingly, the Company regularly reviews and assesses whether warranty reserves should be recorded in the period the related revenue is recorded. For an initial shipment of product for use in a system with new technical demands or new configurations and where the Company is unsure of meeting the customer’s specifications, the Company will defer the recognition of product revenue and related costs until written customer acceptance is obtained.

The Company did not record any warranty expense during the nine months ended September 30, 2020 and 2019. As of September 30, 2020, the Company had satisfied all warranty claims.

Recently Issued Accounting Standards

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies. Recently issued standards typically do not require adoption until a future effective date. Prior to their effective date, the Company evaluates the pronouncements to determine the potential effects of adoption to its consolidated financial statements.

Standards Implemented Since December 31, 2019

The Company has not implemented any accounting standards that had a material impact on its consolidated financial statements during the nine months ended September 30, 2020.

Standards to be Implemented

The Company believes that the impact of recently issued accounting standards that are not yet effective will not have a material impact on its consolidated financial statements.

Revenue from Contracts with Customers

9 Months Ended

Sep. 30, 2020

Revenue From Contract With Customer [Abstract]

Revenue from Contracts with Customers

(3) Revenue from Contracts with Customers

Revenue Recognition

Revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identification of the contract with a customer; (ii) identification of the performance obligations in the contract; (iii) determination of the transaction price; (iv) allocation of the transaction price to the separate performance obligations in the contract; and (v) recognition of the revenue associated with performance obligations as they are satisfied. The Company applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance

obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price based on the estimated relative standalone-selling prices of the promised products or services underlying each performance obligation. The Company determines standalone-selling prices based on the price at which the performance obligation is sold separately. If the standalone-selling price is not observable through past transactions, the Company estimates the standalone-selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. Applying the practical expedient in paragraph ASC 606-10-32-18, the Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. The Company did not have any contracts outstanding at December 31, 2019 and did not enter into any contracts during the nine months ended September 30, 2020 that contained a significant financing component.

The Company records deferred revenue for product sales when (i) the Company has delivered products but other revenue recognition criteria have not been satisfied or (ii) payments have been received in advance of the completion of required performance obligations.

Shipping and Handling Costs

Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as fulfillment costs and are included in the cost of product revenue. The associated amount of revenue recognized includes the consideration to which the Company expects to be entitled to receive in exchange for incurring these shipping and handling costs.

Product Revenue

The Company generally enters into contracts containing one type of performance obligation. The Company recognizes product revenue when the performance obligation is satisfied, which is generally upon delivery according to contractual shipping terms within customer purchase orders.

The Company also enters into rebate agreements with certain customers. These agreements may be considered an additional performance obligation of the Company or variable consideration within a contract. Rebates are recorded as a reduction of revenue in the period the related product revenue is recognized. A corresponding liability is recorded as a component of deferred revenue on the consolidated balance sheets. These arrangements are primarily based on the customer attaining contractually specified sales volumes.

The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using historical rates of return, current quarter credit sales, and specific items of exposure on a contract-by-contract basis. Sales return reserves were approximately $0.1 million at both September 30, 2020 and December 31, 2019.

Subsea Projects

The Company manufactures and sells products that are designed for pipe-in-pipe applications in subsea oil production and are typically customized to meet customer specifications. Subsea products typically have no alternative use and contain an enforceable right to payment. Customer invoicing terms for subsea products are typically based on certain milestones within the production and delivery schedule. Under the provisions of ASC 606, the Company recognizes revenue at a point in time when transfer of control of the products is passed to the customer, or over time utilizing the input method. The timing of revenue recognition is assessed on a contract-by-contract basis. During the nine months ended September 30, 2020 and 2019, the Company recognized revenue of $8.3 million and $14.4 million, respectively, in connection with subsea projects.

Research Services

The Company performs research services under contracts with various government agencies and other institutions. These contracts generally have one type of performance obligation associated with the provision of research services including certain licenses to any resulting intellectual property. The Company records revenue using the percentage-of-completion method in two ways: (1) for firm-fixed-price contracts, the Company accrues that portion of the total contract price that is allocable on the basis of the Company’s estimates of costs incurred to date to total contract costs; and (2) for cost-plus-fixed-fee contracts, the Company records

revenue that is equal to total payroll cost incurred times a stated factor plus reimbursable expenses, to a stated upper limit. The primary cost under the Company’s research service contracts is the labor effort expended in completing the research. Typically, the only deliverable, other than the labor hours expended, is reporting research results to the customer or delivery of research grade aerogel products. Because the input measure of labor hours expended is also reflective of the output measure, it is a reliable means to measure the extent of progress toward completion. Revisions in cost estimates and fees during the course of the contract are reflected in the accounting period in which the facts that require the revisions become known. Contract costs and rates used to allocate overhead to contracts are subject to audit by the respective contracting government agency. Adjustments to revenue as a result of audit are recorded within the period they become known. To date, adjustments to revenue as a result of contracting agency audits have been insignificant.

Disaggregation of Revenue

In the following tables, revenue is disaggregated by primary geographical region and source of revenue:

	Three Months Ended September 30,
	2020						2019
	U.S.		International		Total		U.S.		International		Total
	(In thousands)
Geographical region
Asia	$	—	$	9,617	$	9,617	$	—	$	10,535	$	10,535
Canada		—		25		25		—		5,372		5,372
Europe		—		4,635		4,635		—		3,726		3,726
Latin America		—		182		182		—		601		601
U.S.		9,736		—		9,736		15,191		—		15,191
Total revenue	$	9,736	$	14,459	$	24,195	$	15,191	$	20,234	$	35,425

Source of revenue
Product revenue	$	8,612	$	12,307	$	20,919	$	14,812	$	18,286	$	33,098
Subsea projects		868		2,152		3,020		—		1,948		1,948
Research services		256		—		256		379		—		379
Total revenue	$	9,736	$	14,459	$	24,195	$	15,191	$	20,234	$	35,425

	Nine Months Ended September 30,
	2020						2019
	U.S.		International		Total		U.S.		International		Total
	(In thousands)
Geographical region
Asia	$	—	$	33,373	$	33,373	$	—	$	25,044	$	25,044
Canada		—		715		715		—		7,278		7,278
Europe		—		9,590		9,590		—		16,713		16,713
Latin America		—		2,076		2,076		—		2,420		2,420
U.S.		31,501		—		31,501		41,415		—		41,415
Total revenue	$	31,501	$	45,754	$	77,255	$	41,415	$	51,455	$	92,870

Source of revenue
Product revenue	$	29,039	$	39,394	$	68,433	$	35,727	$	40,585	$	76,312
Subsea projects		1,979		6,360		8,339		3,557		10,870		14,427
Research services		483		—		483		2,131		—		2,131
Total revenue	$	31,501	$	45,754	$	77,255	$	41,415	$	51,455	$	92,870

Contract Balances

The following table presents changes in the Company’s contract assets and contract liabilities during the nine months ended September 30, 2020:

	Balance at December 31, 2019		Additions		Deductions			Balance at September 30, 2020
	(In thousands)
Contract assets
Subsea projects	$	2,811	$	8,254	$	(8,659	)	$	2,406
Research services		172		250		(233	)		189
Total contract assets	$	2,983	$	8,504	$	(8,892	)	$	2,595
Contract liabilities
Deferred revenue
Product revenue	$	4,991	$	997	$	(4,122	)	$	1,866
Subsea projects		491		4,387		(4,469	)		409
Research services		138		94		(232	)		—
Prepayment liability		9,786		—		(218	)		9,568
Total contract liabilities	$	15,406	$	5,478	$	(9,041	)	$	11,843

During the nine months ended September 30, 2020, the Company recognized $4.6 million of revenue that was included in deferred revenue at the beginning of the period.

A contract asset is recorded when the Company satisfies a performance obligation by transferring a promised good or service and has earned the right to consideration from its customer. These assets may represent a conditional or unconditional right to consideration and are included within accounts receivable on the consolidated balance sheets.

A contract liability is recorded when consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services under the terms of the contract. Contract liabilities are recognized as revenue after control of the products or services is transferred to the customer and all revenue recognition criteria have been met.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Inventories

9 Months Ended

Sep. 30, 2020

Inventory Disclosure [Abstract]

Inventories

(4) Inventories

Inventories consist of the following:

	September 30,		December 31,
	2020		2019
	(In thousands)
Raw materials	$	4,847	$	4,334
Finished goods		4,580		4,434
Total	$	9,427	$	8,768

Property, Plant and Equipment, Net

9 Months Ended

Sep. 30, 2020

Property Plant And Equipment [Abstract]

Property, Plant and Equipment, Net

(5) Property, Plant and Equipment, Net

Property, plant and equipment consist of the following:

	September 30,			December 31,			Useful
	2020			2019			life
	(In thousands)
Construction in progress	$	977		$	1,309			—
Buildings		24,016			24,016		30 years
Machinery and equipment		124,681			122,485		3-10 years
Computer equipment and software		8,737			8,556		3 years
Total		158,411			156,366
Accumulated depreciation		(110,312	)		(102,749	)
Property, plant and equipment, net	$	48,099		$	53,617

Depreciation expense was $7.7 million for both the nine months ended September 30, 2020 and 2019.

Accrued Expenses

9 Months Ended

Sep. 30, 2020

Payables And Accruals [Abstract]

Accrued Expenses

(6) Accrued Expenses

Accrued expenses consist of the following:

	September 30,		December 31,
	2020		2019
	(In thousands)
Employee compensation	$	2,401	$	6,472
Other accrued expenses		1,680		1,585
Total	$	4,081	$	8,057

Debt

9 Months Ended

Sep. 30, 2020

Debt Disclosure [Abstract]

Debt

(7) Debt

On May 1, 2020, Aspen Aerogels Rhode Island, LLC (Borrower) executed a promissory note (Note) in favor of Northeast Bank to receive an unsecured loan in the principal amount of $3,685,800 (the PPP Loan) pursuant to the Paycheck Protection Program (PPP) established by the CARES Act, as amended by the Paycheck Protection Program Flexibility Act (Flexibility Act), and administered by the SBA. The Borrower conferred with representatives of the SBA prior to finalizing the PPP Loan. The PPP Loan was subsequently sold by Northeast Bank to The Loan Source, Inc. (PPP Investor), a secondary market investor.

The PPP Loan carries an interest rate of 1% per year and matures two years from the date of the Note. The PPP Loan indebtedness may be forgiven in whole or in part upon application by the Borrower to the PPP Investor. The PPP Investor will determine to what extent the PPP Loan is eligible for forgiveness, subject to SBA guidelines and other regulations, based on the use of loan proceeds for payroll costs, payment of interest on covered mortgage obligations, rent and utility costs over either an eight-week or 24-week period, at the Borrower’s option, following the Borrower’s receipt of the loan proceeds. Upon the Borrower’s application for forgiveness, the SBA will review the Borrower’s eligibility, use of proceeds and other certifications in connection with the application for the PPP Loan. Upon such review, the SBA may approve or deny the Borrower’s loan forgiveness application, in whole or part. As of September 30, 2020, the Borrower had not applied for forgiveness.

If the Borrower has not applied for forgiveness within ten months from the end of the 24-week period following receipt of the loan proceeds, the Borrower shall then be required make payments of principal and accrued interest in equal monthly installments over the remaining term of the loan. In addition, the Flexibility Act permits the Borrower and the PPP Investor to mutually agree to extend the term of the PPP Loan to five years from the date of the Note. The Borrower may repay the PPP Loan at any time without penalty.

While the Borrower is not required to apply for forgiveness of the PPP Loan, upon application for forgiveness, the Borrower may not receive forgiveness of the PPP Loan in whole or in part. In addition, the amount of potential loan forgiveness may be reduced if the Borrower fails to maintain employee and salary levels during the applicable eight-week or 24-week period following receipt of the loan proceeds. If the Borrower applies for forgiveness, and the PPP Loan is not forgiven in whole or only forgiven in part, the Borrower shall then be required to immediately begin making payments of principal and accrued interest in equal monthly installments over the remaining term of the loan for any post-forgiveness balance outstanding.

The Note contains customary events of default relating to, among other things, payment defaults, breaches of representations and warranties, and defaults under any loan or agreement with another debtor, including the Company’s credit facility with SVB, to the extent the PPP Investor believes such default may materially affect the Borrower’s ability to repay the PPP Loan. The occurrence of an event of default, if not cured, may result in the Borrower’s repayment of the PPP Loan prior to maturity.

The Borrower has used the proceeds of the PPP Loan to support ongoing operations and to sustain staffing levels in its East Providence, Rhode Island manufacturing facility despite the unfavorable impact of the COVID-19 pandemic and volatile energy markets on its business.

Long-term debt consists of the following:

	September 30,			December 31,
	2020			2019
	(In thousands)
Long-term debt, principal	$	3,686		$	—
Current portion of long-term debt		(367	)		—
Debt issuance costs, net of accumulated amortization		(21	)		—
Long-term debt	$	3,298		$	—

The schedule of required principal payments remaining on long-term debt outstanding as of September 30, 2020 is as follows:

Year	Principal Payments
	(In thousands)
2020 (excluding the nine months ended September 30, 2020)	$	—
2021		1,609
2022		2,077
Total principal payments	$	3,686

Commitments and Contingencies

9 Months Ended

Sep. 30, 2020

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

(8) Commitments and Contingencies

Thermal Barrier Contract

The Company is party to a contract with a major U.S. automotive original equipment manufacturer (OEM) to supply fabricated, multi-part thermal barriers (Barriers) for use in the battery system of its next-generation electric vehicles (Contract). Pursuant to the Contract, the Company is obligated to supply Barriers at fixed annual prices and at volumes to be specified by the OEM up to a daily maximum quantity through the term of the agreement, which expires on September 1, 2026. While the OEM has agreed to purchase its requirement for Barriers at locations to be designated from time to time from the Company, it has no obligation to purchase any minimum quantity of Barriers under the Contract. In addition, the OEM may terminate the Contract any time and for any or no reason. All other terms of the Contract are generally consistent with the OEM’s standard purchase terms, including customary quality and warranty provisions.

BASF Supply Agreement

The Company is party to a supply agreement, as amended, with BASF Polyurethanes GmbH (BASF) (the Supply Agreement) and a joint development agreement with BASF SE (the JDA). Pursuant to the Supply Agreement, the Company will sell exclusively to BASF certain of the Company’s products at annual volumes to be specified by BASF, subject to certain volume limits. However, BASF has no obligation to purchase products under the Supply Agreement. The Supply Agreement will terminate on December 31, 2027 with respect to the Company’s Spaceloft A2 product and December 31, 2028 with respect to a new product developed under the JDA. Upon the expiration of the Supply Agreement with respect to each product, the Company will be subject to a post-termination supply commitment for an additional two years. The JDA is designed to facilitate collaboration by the parties on the development and commercialization of new products.

In addition, BASF, in its sole discretion, may make prepayments to the Company in the aggregate amount of up to $22.0 million during the term of the Supply Agreement. These prepayment obligations are secured by a security interest in real estate, plant and equipment at the Company’s Rhode Island facility and a license to certain intellectual property. BASF made a prepayment in the amount of $5.0 million to the Company in 2018 (the 2018 Prepayment). As of January 1, 2019, 25.3% of any amounts that the Company invoices for Spaceloft A2 sold to BASF will be credited against the outstanding balance of the 2018 prepayment. If any of the 2018 Prepayment remains uncredited as of December 31, 2021, BASF may require that the Company repay the uncredited amount to BASF.

Pursuant to the first addendum to the Supply Agreement, on January 30, 2019, BASF made an additional prepayment in the amount of $5.0 million to the Company (the 2019 Prepayment). As of January 1, 2020, 50.0% of any amounts that the Company invoices for the newly developed product sold to BASF will be credited against the outstanding balance of the 2019 Prepayment. After December 31, 2022, BASF may require that the Company credit an additional 24.7% of any amounts invoiced by the Company for Spaceloft A2 product sold to BASF against the outstanding balance of the 2019 Prepayment, if any, or may require that the Company repay the uncredited amount of the 2019 Prepayment to BASF in full.

As of September 30, 2020, the Company had received $10.0 million in prepayments from BASF and applied approximately $0.2 million of credits against amounts invoiced. The prepayments are recorded on the balance sheet as a prepayment liability, net of the current portion of $0.3 million at both September 30, 2020 and December 31, 2019, which is included within deferred revenue. The amounts and terms of additional prepayment installments, if any, are subject to negotiation between the Company and BASF.

Revolving Line of Credit

The Company is party to an Amended and Restated Loan and Security Agreement with Silicon Valley Bank (Loan Agreement). On March 3, 2020, the Loan Agreement was amended to extend the maturity date of the revolving credit facility to April 28, 2021. On September 25, 2020, the Loan Agreement was further amended to revise, among other things, the minimum Adjusted EBITDA financial covenant.

Under the revolving credit facility, the Company is permitted to borrow a maximum of $20.0 million, subject to continued covenant compliance and borrowing base requirements. At the Company’s election, the interest rate applicable to borrowings under the revolving credit facility may be based on prime rate or LIBOR, subject to a minimum rate of 4.00% per annum. Prime rate-based rates vary from prime rate plus 0.75% per annum to prime rate plus 2.00% per annum, while LIBOR-based rates vary from LIBOR plus 3.75% per annum to LIBOR plus 4.25% per annum. In addition, the Company is required to pay a monthly unused revolving line of credit facility fee of 0.5% per annum of the average unused portion of the revolving credit facility.

Under the Loan Agreement, the Company is required to comply with both non-financial and financial covenants, including a minimum Adjusted EBITDA covenant, as defined. At September 30, 2020, the Company was in compliance with all such covenants. Obligations under the Loan Agreement are secured by a security interest in all assets of the Company, including those at the East Providence facility, except for certain exclusions. The Company intends to extend or replace the facility prior to its maturity.

At September 30, 2020 and December 31, 2019, the Company had zero dollars and $3.1 million, respectively, drawn on the revolving credit facility. In addition, the Company has been required to provide letters of credit to secure obligations under certain commercial contracts and other obligations. The Company had outstanding letters of credit backed by the revolving credit facility of $1.4 million and $0.9 million at September 30, 2020 and December 31, 2019, respectively, which reduce the funds otherwise available to the Company under the facility.

At September 30, 2020, the amount available to the Company under the revolving credit facility was $8.1 million after giving effect to $1.4 million of outstanding letters of credit.

Federal, State and Local Environmental Regulations

The Company is subject to federal, state and local laws and regulations relating to the environment. These laws generally provide for control of pollutants released into the environment and require responsible parties to undertake remediation. Penalties may be imposed for noncompliance.

The Company is currently in technical discussions with the U.S. Environmental Protection Agency (EPA) in connection with the EPA’s notice of potential violation and opportunity to confer that the Company received regarding the applicability of certain Resource Conservation and Recovery Act (RCRA) provisions to certain aspects of its manufacturing unit operations. The EPA notice is in connection with the EPA’s RCRA Compliance Evaluation Inspection of the Company’s East Providence, Rhode Island manufacturing facility in May 2019. While the Company believes its environmental compliance program is consistent with the RCRA statutory and regulatory framework, the EPA may decide otherwise, find the Company in violation, assess penalties and compel compliance that may require capital expenditure and resource allocation that may have a material impact on the Company. However, at present, the EPA has not made any determination as to any violation and the Company does not know when the EPA may make any determination. As such, the Company has determined that while it is possible it will incur expense in this regard, whether any expense will be incurred, its nature, or any amount is not estimable as of September 30, 2020.

Litigation

The Company is, from time to time, a party to litigation that arises in the normal course of its business operations. See Part II, Item 1 “Legal Proceedings” of this Quarterly Report on Form 10-Q for a description of certain of the Company’s current legal proceedings. The Company is not presently a party to any litigation for which it believes a loss is probable requiring an amount to be accrued or a possible loss contingency requiring disclosure.

Leases

9 Months Ended

Sep. 30, 2020

Leases [Abstract]

Leases

(9) Leases

The Company leases office and warehouse space in Northborough, Massachusetts and East Providence, Rhode Island under operating leases. Under these agreements, the Company is obligated to pay annual rent, real estate taxes, and certain other operating expenses. The Company also leases equipment under operating leases. The Company’s operating leases expire at various dates through 2026.

On January 1, 2019, the Company adopted ASU 2016-02 which modifies the accounting for leases and requires that all leases be recorded on the consolidated balance sheets as assets and liabilities. The Company adopted this standard using the modified retrospective transition approach with the effective date as the date of initial application. The Company also elected the package of practical expedients under the new standard, which permits the Company to not reassess prior conclusions about lease identification, lease classification, and initial direct costs. In addition, the Company elected the short-term lease recognition exemption under which the Company will not recognize right-of-use (ROU) assets or lease liabilities for all leases that qualify. The Company also elected the practical expedient to not separate non-lease components from the associated lease components for all of its equipment leases.

The Company determines if an arrangement is a lease at inception. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s payment obligations under the lease. Operating lease ROU assets and liabilities are recognized based on the present value of lease payments over the lease term. To measure its lease liabilities, the Company uses its incremental borrowing rate or the rate implicit in the lease, if available. The Company calculates its incremental borrowing rate using a synthetic credit rating analysis based on Moody’s Building Materials Industry Rating Methodology. ROU assets also include any direct costs and prepaid lease payments but exclude any lease incentives received. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.

The Company elected the short-term lease recognition exemption for all leases that qualify. For leases that qualify for this exemption, the Company does not recognize ROU assets or lease liabilities. For lease agreements with lease and non-lease components, the Company accounts for each component separately. However, in the case of equipment leases, the Company accounts for lease and non-lease components as a single component.

Upon adoption of ASU 2016-02 on January 1, 2019, the Company recognized operating lease liabilities of approximately $6.0 million with corresponding ROU assets of approximately $4.6 million. Additionally, the Company derecognized deferred rent liabilities of $1.4 million.

Maturities of operating lease liabilities at September 30, 2020 are as follows:

Year	Operating Leases
	(In thousands)
2020 (excluding the nine months ended September 30, 2020)	$	376
2021		1,331
2022		1,249
2023		1,193
2024		684
Thereafter		1,049
Total lease payments		5,882
Less imputed interest		(981	)
Total lease liabilities	$	4,901

The Company incurred operating lease costs of $1.1 million and $1.2 million during the nine months ended September 30, 2020 and 2019, respectively. Cash payments related to operating lease liabilities were $1.1 million during both the nine months ended September 30, 2020 and 2019.

At September 30, 2020, the weighted average remaining lease term for operating leases was 4.8 years. At September 30, 2020, the weighted average discount rate for operating leases was 7.7%.

Other Long-Term Liabilities

9 Months Ended

Sep. 30, 2020

Other Liabilities Disclosure [Abstract]

Other Long-Term Liabilities

(10) Other Long-Term Liabilities

Other long-term liabilities of $0.6 million consist of the Company’s employer payroll tax obligation for the period from March 27, 2020 to September 30, 2020 on which payment was deferred pursuant to the provisions of the CARES Act. The Company is required to remit 50 percent of the deferred tax balance as of December 31, 2020 on or before December 31, 2021 and the remaining 50 percent on or before December 31, 2022.

Net Loss Per Share

9 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Net Loss Per Share

(11) Net Loss Per Share

The computation of basic and diluted net loss per share consists of the following:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2020			2019			2020			2019
	(In thousands, except share and per share data)
Numerator:
Net loss	$	(6,753	)	$	(2,289	)	$	(15,620	)	$	(13,609	)
Denominator:
Weighted average shares outstanding, basic and diluted		26,728,205			24,171,811			26,150,236			24,074,565
Net loss per share, basic and diluted	$	(0.25	)	$	(0.09	)	$	(0.60	)	$	(0.57	)

Potentially dilutive common shares that were excluded from the computation of diluted net loss per share because they were anti-dilutive consist of the following:

	Three and Nine Months Ended
	September 30,
	2020		2019
Common stock options		3,918,669		3,683,858
Restricted common stock units		699,559		1,105,415
Restricted common stock awards		123,191		128,453
Total		4,741,419		4,917,726

In the table above, anti-dilutive shares consist of those common stock equivalents that have (i) an exercise price above the average stock price for the period or (ii) related average unrecognized stock compensation expense sufficient to buy back the entire amount of shares. The Company excludes the shares issued in connection with restricted stock awards from the calculation of basic weighted average common shares outstanding until the restrictions lapse.

Income Taxes

9 Months Ended

Sep. 30, 2020

Income Tax Disclosure [Abstract]

Income Taxes

(12) Income Taxes

The Company incurred net operating losses and recorded a full valuation allowance against net deferred tax assets for all periods presented. Accordingly, the Company has not recorded a provision for federal or state income taxes.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Subsequent Events

9 Months Ended

Sep. 30, 2020

Subsequent Events [Abstract]

Subsequent Events

(13) Subsequent Events

The Company has evaluated subsequent events through November 5, 2020, the date of issuance of the consolidated financial statements for the three and nine months ended September 30, 2020.

On November 5, 2020, the Company entered into a sales agreement with B. Riley Securities, Inc. (B. Riley), as sales agent, pursuant to which the Company may offer and sell, from time to time, through B. Riley, shares of the Company’s common stock, having an aggregate offering price of up to $33,871,250.

Description of Business and Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Nature of Business

Aspen Aerogels, Inc. (the Company) is an aerogel technology company that designs, develops and manufactures innovative, high-performance aerogel insulation used primarily in the energy infrastructure and building materials markets. In addition, the Company is developing high value applications for its aerogel technology in the electric vehicle market. The Company also conducts research related to aerogel technology supported by funding from several agencies of the U.S. government and other institutions in the form of research contracts. The Company has decided to cease efforts to secure additional funded research contracts and to wind down existing contract research activities.

The Company maintains its corporate offices in Northborough, Massachusetts. The Company has three wholly owned subsidiaries: Aspen Aerogels Rhode Island, LLC, Aspen Aerogels Germany, GmbH and Aspen Aerogels Georgia, LLC.

Liquidity

During the nine months ended September 30, 2020, the Company incurred a net loss of $15.6 million and used $4.8 million of cash in operations. On February 18, 2020, the Company received net proceeds of $14.8 million upon the completion of an underwritten public offering of the Company’s common stock. On May 4, 2020, Aspen Aerogels Rhode Island, LLC received loan proceeds of $3.7 million upon the execution of a promissory note pursuant to the Paycheck Protection Program (PPP) established by the Coronavirus Aid, Relief and Economic Security Act (CARES Act) and administered by the U.S. Small Business Administration (SBA) (see note 7). The Company had cash and cash equivalents of $11.3 million, total debt of $3.7 million and no outstanding borrowings under its revolving line of credit as of September 30, 2020 (see note 8). After giving effect to $1.4 million of outstanding letters of credit, the amount available to the Company at September 30, 2020 under the revolving line of credit was $8.1 million. The existing revolving line of credit matures on April 28, 2021.

The Company is increasing investment in the research and development of next-generation aerogel products and manufacturing process technologies. The Company is developing aerogel products and technologies for the electric vehicle market. The commercial potential for the Company’s technology in the electric vehicle market is significant and could require the Company to hire additional personnel, incur additional operating expenses, and incur capital expenditures to expand aerogel manufacturing capacity, build an automated fabrication operation, and meet automotive quality system requirements, among other items.

The Company expects its existing cash balance and the amount anticipated to be available under the existing revolving line of credit will be sufficient to support current operating requirements and research and development activities. However, the Company plans to supplement its cash balance and available credit with debt financings, customer prepayments, technology licensing fees or equity financings to provide the capital necessary to fund the evolving commercial opportunity in the electric vehicle market and other strategic business opportunities.

Unaudited Interim Financial Information

The accompanying unaudited interim consolidated financial statements include the accounts of the Company and have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Certain information and disclosures normally included in the consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the audited consolidated financial statements and accompanying notes in our Annual Report on Form 10-K for the year ended December 31, 2019 (the Annual Report), filed with the U.S. Securities and Exchange Commission on March 6, 2020.

In the opinion of the Company’s management, the unaudited interim consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and include all adjustments that are of a normal recurring nature and necessary for the fair statement of the Company’s financial position as of September 30, 2020 and the results of its operations and stockholders’ equity for the three and nine months ended September 30, 2020 and 2019 and the cash flows for the nine month periods then ended. The Company has evaluated subsequent events through the date of this filing.

The Company’s results of operations for the three and nine months ended September 30, 2020 are not necessarily indicative of the results to be expected for the year ending December 31, 2020 or any other period. In addition, the Company is uncertain of the ultimate duration and severity of the COVID-19 pandemic and recent global oil market volatility, and the impact they will have on the Company’s results of operations for the year ending December 31, 2020 or any other period.

Principles of Consolidation

The accompanying consolidated financial statements, which have been prepared in accordance with U.S. GAAP, include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of the consolidated financial statements requires the Company to make a number of estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include allowances for doubtful accounts, sales returns and allowances, product warranty costs, inventory valuation, the carrying amount of property and equipment, stock-based compensation and deferred income taxes. The Company evaluates its estimates and assumptions on an on-going basis using historical experience and other factors, including current economic conditions, which are believed to be reasonable under the circumstances. Management adjusts such estimates and assumptions when facts and circumstances warrant. Illiquid credit markets, volatile equity markets and declines in business investment can increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in these estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods.

Cash and Cash Equivalents

Cash equivalents include short-term, highly liquid instruments, which consist of money market accounts. All cash and cash equivalents are maintained with major financial institutions in North America. Deposits with these financial institutions may exceed the amount of insurance provided on such deposits; however, these deposits typically may be redeemed upon demand and, therefore, bear minimal risk.

Concentration of Credit Risk

Financial instruments, which potentially expose the Company to concentrations of credit risk, consist principally of accounts receivable. The Company maintains an allowance for doubtful accounts based on its assessment of the collectability of accounts receivable. The Company reviews the allowance for doubtful accounts quarterly. During the nine months ended September 30, 2020, the Company recorded a charge for estimated customer uncollectible accounts receivable of $0.2 million. The Company did not record a charge for uncollectible accounts receivable during the nine months ended September 30, 2019.

Revenue Recognition

The Company recognizes revenue in accordance with Accounting Standards Codification 606, Revenue from Contracts with Customers (ASC 606). See note 3 for further details.

Revenue Recognition

Revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identification of the contract with a customer; (ii) identification of the performance obligations in the contract; (iii) determination of the transaction price; (iv) allocation of the transaction price to the separate performance obligations in the contract; and (v) recognition of the revenue associated with performance obligations as they are satisfied. The Company applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance

obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price based on the estimated relative standalone-selling prices of the promised products or services underlying each performance obligation. The Company determines standalone-selling prices based on the price at which the performance obligation is sold separately. If the standalone-selling price is not observable through past transactions, the Company estimates the standalone-selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. Applying the practical expedient in paragraph ASC 606-10-32-18, the Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. The Company did not have any contracts outstanding at December 31, 2019 and did not enter into any contracts during the nine months ended September 30, 2020 that contained a significant financing component.

The Company records deferred revenue for product sales when (i) the Company has delivered products but other revenue recognition criteria have not been satisfied or (ii) payments have been received in advance of the completion of required performance obligations.

Shipping and Handling Costs

Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as fulfillment costs and are included in the cost of product revenue. The associated amount of revenue recognized includes the consideration to which the Company expects to be entitled to receive in exchange for incurring these shipping and handling costs.

Product Revenue

The Company generally enters into contracts containing one type of performance obligation. The Company recognizes product revenue when the performance obligation is satisfied, which is generally upon delivery according to contractual shipping terms within customer purchase orders.

The Company also enters into rebate agreements with certain customers. These agreements may be considered an additional performance obligation of the Company or variable consideration within a contract. Rebates are recorded as a reduction of revenue in the period the related product revenue is recognized. A corresponding liability is recorded as a component of deferred revenue on the consolidated balance sheets. These arrangements are primarily based on the customer attaining contractually specified sales volumes.

The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using historical rates of return, current quarter credit sales, and specific items of exposure on a contract-by-contract basis. Sales return reserves were approximately $0.1 million at both September 30, 2020 and December 31, 2019.

Subsea Projects

The Company manufactures and sells products that are designed for pipe-in-pipe applications in subsea oil production and are typically customized to meet customer specifications. Subsea products typically have no alternative use and contain an enforceable right to payment. Customer invoicing terms for subsea products are typically based on certain milestones within the production and delivery schedule. Under the provisions of ASC 606, the Company recognizes revenue at a point in time when transfer of control of the products is passed to the customer, or over time utilizing the input method. The timing of revenue recognition is assessed on a contract-by-contract basis. During the nine months ended September 30, 2020 and 2019, the Company recognized revenue of $8.3 million and $14.4 million, respectively, in connection with subsea projects.

Research Services

The Company performs research services under contracts with various government agencies and other institutions. These contracts generally have one type of performance obligation associated with the provision of research services including certain licenses to any resulting intellectual property. The Company records revenue using the percentage-of-completion method in two ways: (1) for firm-fixed-price contracts, the Company accrues that portion of the total contract price that is allocable on the basis of the Company’s estimates of costs incurred to date to total contract costs; and (2) for cost-plus-fixed-fee contracts, the Company records

revenue that is equal to total payroll cost incurred times a stated factor plus reimbursable expenses, to a stated upper limit. The primary cost under the Company’s research service contracts is the labor effort expended in completing the research. Typically, the only deliverable, other than the labor hours expended, is reporting research results to the customer or delivery of research grade aerogel products. Because the input measure of labor hours expended is also reflective of the output measure, it is a reliable means to measure the extent of progress toward completion. Revisions in cost estimates and fees during the course of the contract are reflected in the accounting period in which the facts that require the revisions become known. Contract costs and rates used to allocate overhead to contracts are subject to audit by the respective contracting government agency. Adjustments to revenue as a result of audit are recorded within the period they become known. To date, adjustments to revenue as a result of contracting agency audits have been insignificant.

Leases

On January 1, 2019, the Company adopted Accounting Standards Update (ASU) 2016-02, Leases (Topic 842). See note 9 for further details.

On January 1, 2019, the Company adopted ASU 2016-02 which modifies the accounting for leases and requires that all leases be recorded on the consolidated balance sheets as assets and liabilities. The Company adopted this standard using the modified retrospective transition approach with the effective date as the date of initial application. The Company also elected the package of practical expedients under the new standard, which permits the Company to not reassess prior conclusions about lease identification, lease classification, and initial direct costs. In addition, the Company elected the short-term lease recognition exemption under which the Company will not recognize right-of-use (ROU) assets or lease liabilities for all leases that qualify. The Company also elected the practical expedient to not separate non-lease components from the associated lease components for all of its equipment leases.

The Company determines if an arrangement is a lease at inception. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s payment obligations under the lease. Operating lease ROU assets and liabilities are recognized based on the present value of lease payments over the lease term. To measure its lease liabilities, the Company uses its incremental borrowing rate or the rate implicit in the lease, if available. The Company calculates its incremental borrowing rate using a synthetic credit rating analysis based on Moody’s Building Materials Industry Rating Methodology. ROU assets also include any direct costs and prepaid lease payments but exclude any lease incentives received. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.

The Company elected the short-term lease recognition exemption for all leases that qualify. For leases that qualify for this exemption, the Company does not recognize ROU assets or lease liabilities. For lease agreements with lease and non-lease components, the Company accounts for each component separately. However, in the case of equipment leases, the Company accounts for lease and non-lease components as a single component.

Stock-based Compensation

Stock-based compensation expense is measured at the grant date based on the fair value of the award. Expense is recognized on a straight-line basis over the requisite service period for all awards with service conditions. For performance-based awards, the grant date fair value is recognized as expense when the condition is probable of being achieved and then on a graded basis over the requisite service period. The Company uses the Black-Scholes option-pricing model to determine the fair value of service-based option awards, which requires a number of complex and subjective assumptions including fair value of the underlying security, the expected volatility

of the underlying security, a risk-free interest rate and the expected term of the option. The fair value of restricted stock and restricted stock unit grants is determined using the closing trading price of the Company’s common stock on the date of grant. The fair value of awards containing market conditions is determined using a Monte Carlo simulation model based upon the nature of the conditions, the expected volatility of the underlying security, and other relevant factors.

During the nine months ended September 30, 2020, the Company granted 165,430 restricted common stock units (RSUs) with a grant date fair value of $1.3 million and non-qualified stock options (NSOs) to purchase 617,627 shares of common stock with a grant date fair value of $2.4 million to employees under the 2014 Employee, Director, and Consultant Equity Incentive Plan (the 2014 Equity Plan). The RSUs and NSOs granted to employees will vest over a three-year period. During the nine months ended September 30, 2020, the Company also granted 45,066 shares of restricted common stock with a grant date fair value of $0.3 million and NSOs to purchase 58,902 shares of common stock with a grant date fair value of $0.2 million to its non-employee directors under the 2014 Equity Plan. The restricted common stock and NSOs granted to non-employee directors will vest upon the earlier of the date that is the one-year anniversary of the grant or the day prior to the Company’s annual meeting of stockholders to be held in 2021.

Stock-based compensation is included in cost of revenue or operating expenses, as applicable, and consists of the following:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Cost of product revenue	$	98	$	125	$	544	$	365
Research and development expenses		169		130		482		374
Sales and marketing expenses		179		168		524		461
General and administrative expenses		545		588		1,440		1,685
Total stock-based compensation	$	991	$	1,011	$	2,990	$	2,885

Pursuant to the “evergreen” provisions of the 2014 Equity Plan, the number of shares of common stock authorized for issuance under the plan automatically increased by 486,050 shares to 7,974,980 shares effective January 1, 2020.

As of September 30, 2020, 4,536,565 shares of common stock were reserved for issuance upon the exercise or vesting of outstanding stock-based awards granted under the 2014 Equity Plan. In addition, as of September 30, 2020, 81,663 shares of common stock were reserved for issuance upon the exercise of outstanding stock options granted under the Company’s 2001 Equity Incentive Plan, as amended (the 2001 Equity Plan). Any cancellations or forfeitures of the options outstanding under the 2001 Equity Plan will result in the shares reserved for issuance upon exercise of such options becoming available for grant under the 2014 Equity Plan. As of September 30, 2020, the Company has either reserved in connection with statutory tax withholdings or issued a total of 2,546,810 shares under the 2014 Equity Plan. As of September 30, 2020, there were 809,942 shares of common stock available for future grant under the 2014 Equity Plan.

Net Loss per Share

The Company calculates net loss per share of common stock based on the weighted-average number of shares of common stock outstanding during each period. Potential common stock equivalents are determined using the treasury stock method. The weighted-average number of shares of common stock included in the computation of diluted net loss gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and RSUs. Common equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive.

Segments

Operating segments are identified as components of an enterprise about which separate, discrete financial information is available for evaluation by the chief operating decision maker in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company’s chief operating decision maker reviews consolidated operating results to make decisions about allocating resources and assessing performance for the entire Company. The Company views its operations and manages its business as one operating segment.

Information about the Company’s total revenues, based on shipment destination or services location, is presented in the following table:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Revenue:
U.S.	$	9,736	$	15,191	$	31,501	$	41,415
International		14,459		20,234		45,754		51,455
Total	$	24,195	$	35,425	$	77,255	$	92,870

Warranty

The Company provides warranties for its products and records the estimated cost within cost of revenue in the period that the related revenue is recorded. The Company’s standard warranty period extends to one year from the date of shipment. This standard warranty provides that the Company’s products will be free from defects in material and workmanship, and will, under normal use, conform to the specifications for the product.

The Company’s products may be utilized in systems that involve new technical demands and new configurations. Accordingly, the Company regularly reviews and assesses whether warranty reserves should be recorded in the period the related revenue is recorded. For an initial shipment of product for use in a system with new technical demands or new configurations and where the Company is unsure of meeting the customer’s specifications, the Company will defer the recognition of product revenue and related costs until written customer acceptance is obtained.

The Company did not record any warranty expense during the nine months ended September 30, 2020 and 2019. As of September 30, 2020, the Company had satisfied all warranty claims.

Recently Issued Accounting Standards

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies. Recently issued standards typically do not require adoption until a future effective date. Prior to their effective date, the Company evaluates the pronouncements to determine the potential effects of adoption to its consolidated financial statements.

Standards Implemented Since December 31, 2019

The Company has not implemented any accounting standards that had a material impact on its consolidated financial statements during the nine months ended September 30, 2020.

Standards to be Implemented

The Company believes that the impact of recently issued accounting standards that are not yet effective will not have a material impact on its consolidated financial statements.

Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Summary of Stock Based Compensation Included in Cost of Revenue or Operating Expenses

Stock-based compensation is included in cost of revenue or operating expenses, as applicable, and consists of the following:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Cost of product revenue	$	98	$	125	$	544	$	365
Research and development expenses		169		130		482		374
Sales and marketing expenses		179		168		524		461
General and administrative expenses		545		588		1,440		1,685
Total stock-based compensation	$	991	$	1,011	$	2,990	$	2,885

Schedule of Revenues, Based on Shipment Destination or Research Services Location

Information about the Company’s total revenues, based on shipment destination or services location, is presented in the following table:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
	(In thousands)
Revenue:
U.S.	$	9,736	$	15,191	$	31,501	$	41,415
International		14,459		20,234		45,754		51,455
Total	$	24,195	$	35,425	$	77,255	$	92,870

Revenue from Contracts with Customers (Tables)

9 Months Ended

Sep. 30, 2020

Revenue From Contract With Customer [Abstract]

Summary of Revenue Disaggregated by Geographical Region and Source of Revenue

In the following tables, revenue is disaggregated by primary geographical region and source of revenue:

	Three Months Ended September 30,
	2020						2019
	U.S.		International		Total		U.S.		International		Total
	(In thousands)
Geographical region
Asia	$	—	$	9,617	$	9,617	$	—	$	10,535	$	10,535
Canada		—		25		25		—		5,372		5,372
Europe		—		4,635		4,635		—		3,726		3,726
Latin America		—		182		182		—		601		601
U.S.		9,736		—		9,736		15,191		—		15,191
Total revenue	$	9,736	$	14,459	$	24,195	$	15,191	$	20,234	$	35,425

Source of revenue
Product revenue	$	8,612	$	12,307	$	20,919	$	14,812	$	18,286	$	33,098
Subsea projects		868		2,152		3,020		—		1,948		1,948
Research services		256		—		256		379		—		379
Total revenue	$	9,736	$	14,459	$	24,195	$	15,191	$	20,234	$	35,425

	Nine Months Ended September 30,
	2020						2019
	U.S.		International		Total		U.S.		International		Total
	(In thousands)
Geographical region
Asia	$	—	$	33,373	$	33,373	$	—	$	25,044	$	25,044
Canada		—		715		715		—		7,278		7,278
Europe		—		9,590		9,590		—		16,713		16,713
Latin America		—		2,076		2,076		—		2,420		2,420
U.S.		31,501		—		31,501		41,415		—		41,415
Total revenue	$	31,501	$	45,754	$	77,255	$	41,415	$	51,455	$	92,870

Source of revenue
Product revenue	$	29,039	$	39,394	$	68,433	$	35,727	$	40,585	$	76,312
Subsea projects		1,979		6,360		8,339		3,557		10,870		14,427
Research services		483		—		483		2,131		—		2,131
Total revenue	$	31,501	$	45,754	$	77,255	$	41,415	$	51,455	$	92,870

Summary of Changes in Contract Assets and Contract Liabilities

The following table presents changes in the Company’s contract assets and contract liabilities during the nine months ended September 30, 2020:

	Balance at December 31, 2019		Additions		Deductions			Balance at September 30, 2020
	(In thousands)
Contract assets
Subsea projects	$	2,811	$	8,254	$	(8,659	)	$	2,406
Research services		172		250		(233	)		189
Total contract assets	$	2,983	$	8,504	$	(8,892	)	$	2,595
Contract liabilities
Deferred revenue
Product revenue	$	4,991	$	997	$	(4,122	)	$	1,866
Subsea projects		491		4,387		(4,469	)		409
Research services		138		94		(232	)		—
Prepayment liability		9,786		—		(218	)		9,568
Total contract liabilities	$	15,406	$	5,478	$	(9,041	)	$	11,843

Inventories (Tables)

9 Months Ended

Sep. 30, 2020

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories consist of the following:

	September 30,		December 31,
	2020		2019
	(In thousands)
Raw materials	$	4,847	$	4,334
Finished goods		4,580		4,434
Total	$	9,427	$	8,768

Property, Plant and Equipment, Net (Tables)

9 Months Ended

Sep. 30, 2020

Property Plant And Equipment [Abstract]

Summary of Property, Plant and Equipment

Property, plant and equipment consist of the following:

	September 30,			December 31,			Useful
	2020			2019			life
	(In thousands)
Construction in progress	$	977		$	1,309			—
Buildings		24,016			24,016		30 years
Machinery and equipment		124,681			122,485		3-10 years
Computer equipment and software		8,737			8,556		3 years
Total		158,411			156,366
Accumulated depreciation		(110,312	)		(102,749	)
Property, plant and equipment, net	$	48,099		$	53,617

Accrued Expenses (Tables)

9 Months Ended

Sep. 30, 2020

Payables And Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following:

	September 30,		December 31,
	2020		2019
	(In thousands)
Employee compensation	$	2,401	$	6,472
Other accrued expenses		1,680		1,585
Total	$	4,081	$	8,057

Debt (Tables)

9 Months Ended

Sep. 30, 2020

Debt Disclosure [Abstract]

Schedule of Long-term Debt

Long-term debt consists of the following:

	September 30,			December 31,
	2020			2019
	(In thousands)
Long-term debt, principal	$	3,686		$	—
Current portion of long-term debt		(367	)		—
Debt issuance costs, net of accumulated amortization		(21	)		—
Long-term debt	$	3,298		$	—

Schedule of Required Principal Payments Remaining on Long-term Debt Outstanding

The schedule of required principal payments remaining on long-term debt outstanding as of September 30, 2020 is as follows:

Year	Principal Payments
	(In thousands)
2020 (excluding the nine months ended September 30, 2020)	$	—
2021		1,609
2022		2,077
Total principal payments	$	3,686

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Leases (Tables)

9 Months Ended

Sep. 30, 2020

Leases [Abstract]

Summary of Maturities of Operating Lease Liabilities

Maturities of operating lease liabilities at September 30, 2020 are as follows:

Year	Operating Leases
	(In thousands)
2020 (excluding the nine months ended September 30, 2020)	$	376
2021		1,331
2022		1,249
2023		1,193
2024		684
Thereafter		1,049
Total lease payments		5,882
Less imputed interest		(981	)
Total lease liabilities	$	4,901

Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Loss Per Share

The computation of basic and diluted net loss per share consists of the following:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2020			2019			2020			2019
	(In thousands, except share and per share data)
Numerator:
Net loss	$	(6,753	)	$	(2,289	)	$	(15,620	)	$	(13,609	)
Denominator:
Weighted average shares outstanding, basic and diluted		26,728,205			24,171,811			26,150,236			24,074,565
Net loss per share, basic and diluted	$	(0.25	)	$	(0.09	)	$	(0.60	)	$	(0.57	)

Summary of Potentially Dilutive Common Shares Excluded from Computation of Diluted Net Loss Per Share

Potentially dilutive common shares that were excluded from the computation of diluted net loss per share because they were anti-dilutive consist of the following:

	Three and Nine Months Ended
	September 30,
	2020		2019
Common stock options		3,918,669		3,683,858
Restricted common stock units		699,559		1,105,415
Restricted common stock awards		123,191		128,453
Total		4,741,419		4,917,726

Description of Business and Basis of Presentation - Additional Information (Detail)			3 Months Ended						9 Months Ended
	May 04, 2020 USD ($)	Feb. 18, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) Subsidiary	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Basis Of Presentation [Line Items]
Number of Subsidiaries \| Subsidiary									3
Net loss incurred			$ 6,753,000	$ 5,698,000	$ 3,169,000	$ 2,289,000	$ 5,318,000	$ 6,002,000	$ 15,620,000	$ 13,609,000
Cash used in operations									4,782,000	$ 5,761,000
Net proceeds upon completion of underwritten public offering		$ 14,800,000							15,036,000
Cash and cash equivalents			11,314,000						11,314,000		$ 3,633,000
Total debt			3,700,000						3,700,000
Outstanding borrowings under revolving line of credit											$ 3,123,000
Aspen Aerogels Rhode Island, LLC [Member] \| Paycheck Protection Program Loan [Member]
Basis Of Presentation [Line Items]
Loan proceeds received upon execution of a promissory note	$ 3,700,000
Revolving Credit Facility [Member]
Basis Of Presentation [Line Items]
Outstanding borrowings under revolving line of credit			0						0
Letters of credit outstanding			1,400,000						1,400,000
Amount available under revolving line of credit			$ 8,100,000						$ 8,100,000
Existing maturity date									Apr. 28, 2021

Significant Accounting Policies - Additional Information (Detail)		9 Months Ended
	Jan. 01, 2020 shares	Sep. 30, 2020 USD ($) Segment shares	Sep. 30, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Charge for uncollectible accounts receivable \| $		$ 171,000	$ 0
Number of segment \| Segment		1
Standard product warranty period		1 year
Warranty expense \| $		$ 0	$ 0
2014 Equity Plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Authorized for issuance, number of shares increased by	486,050
Increased number of shares authorized for grant	7,974,980
Shares reserved for issuance		4,536,565
Number of shares either issued or reserved in connection with statutory tax withholdings		2,546,810
Increased number of shares available for grant		809,942
2014 Equity Plan [Member] \| Non-Qualified Stock Options [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		617,627
Stock-based awards granted to purchase common stock, grant date fair value \| $		$ 2,400,000
Stock-based award vesting period		3 years
2014 Equity Plan [Member] \| Non-Qualified Stock Options [Member] \| Non-employee Directors [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		58,902
Stock-based awards granted to purchase common stock, grant date fair value \| $		$ 200,000
Stock-based award vesting period		1 year
2014 Equity Plan [Member] \| Restricted Stock Units [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		165,430
Stock-based awards granted to purchase common stock, grant date fair value \| $		$ 1,300,000
Stock-based award vesting period		3 years
2014 Equity Plan [Member] \| Restricted Stock Units [Member] \| Non-employee Directors [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		45,066
Stock-based awards granted to purchase common stock, grant date fair value \| $		$ 300,000
Stock-based award vesting period		1 year
2001 Equity Incentive Plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares reserved for issuance		81,663

Significant Accounting Policies - Summary of Stock Based Compensation Included in Cost of Revenue or Operating Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 991	$ 1,011	$ 2,990	$ 2,885
Cost of Product Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	98	125	544	365
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	169	130	482	374
Sales and Marketing Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	179	168	524	461
General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 545	$ 588	$ 1,440	$ 1,685

Significant Accounting Policies - Schedule of Revenues, Based on Shipment Destination or Research Services Location (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 24,195	$ 35,425	$ 77,255	$ 92,870
U.S. [Member]
Segment Reporting Information [Line Items]
Revenue	9,736	15,191	31,501	41,415
International [Member]
Segment Reporting Information [Line Items]
Revenue	$ 14,459	$ 20,234	$ 45,754	$ 51,455

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Revenue from Contracts with Customers - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Agreement	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Revenue Recognition [Line Items]
Revenue	$ 24,195	$ 35,425	$ 77,255	$ 92,870
Deferred revenue, revenue recognized			4,600
Maximum [Member]
Revenue Recognition [Line Items]
Sales return reserves	100		$ 100		$ 100
Product Revenue [Member]
Revenue Recognition [Line Items]
Number of performance obligations \| Agreement			1
Revenue	20,919	33,098	$ 68,433	76,312
Subsea Projects [Member]
Revenue Recognition [Line Items]
Revenue	3,020	1,948	$ 8,339	14,427
Research Services [Member]
Revenue Recognition [Line Items]
Number of performance obligations \| Agreement			1
Revenue	$ 256	$ 379	$ 483	$ 2,131

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Revenue from Contracts with Customers - Summary of Revenue Disaggregated by Geographical Region and Source of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Total revenue	$ 24,195	$ 35,425	$ 77,255	$ 92,870
Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	20,919	33,098	68,433	76,312
Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	3,020	1,948	8,339	14,427
Research Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	256	379	483	2,131
Asia [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	9,617	10,535	33,373	25,044
Canada [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	25	5,372	715	7,278
Europe [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	4,635	3,726	9,590	16,713
Latin America [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	182	601	2,076	2,420
U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	9,736	15,191	31,501	41,415
U.S. [Member] \| Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	8,612	14,812	29,039	35,727
U.S. [Member] \| Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	868		1,979	3,557
U.S. [Member] \| Research Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	256	379	483	2,131
International [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	14,459	20,234	45,754	51,455
International [Member] \| Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	12,307	18,286	39,394	40,585
International [Member] \| Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 2,152	$ 1,948	$ 6,360	$ 10,870

Revenue from Contracts with Customers - Summary of Changes in Contract Assets and Contract Liabilities (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($)
Contract assets
Beginning Balance	$ 2,983
Additions	8,504
Deductions	(8,892)
Ending Balance	2,595
Contract liabilities
Beginning Balance	15,406
Additions	5,478
Deductions	(9,041)
Ending Balance	11,843
Subsea Projects [Member]
Contract assets
Beginning Balance	2,811
Additions	8,254
Deductions	(8,659)
Ending Balance	2,406
Contract liabilities
Beginning Balance	491
Additions	4,387
Deductions	(4,469)
Ending Balance	409
Research Services [Member]
Contract assets
Beginning Balance	172
Additions	250
Deductions	(233)
Ending Balance	189
Contract liabilities
Beginning Balance	138
Additions	94
Deductions	(232)
Product Revenue [Member]
Contract liabilities
Beginning Balance	4,991
Additions	997
Deductions	(4,122)
Ending Balance	1,866
Prepayment Liability [Member]
Contract liabilities
Beginning Balance	9,786
Deductions	(218)
Ending Balance	$ 9,568

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 4,847	$ 4,334
Finished goods	4,580	4,434
Total	$ 9,427	$ 8,768

Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 158,411	$ 156,366
Accumulated depreciation	(110,312)	(102,749)
Property, plant and equipment, net	48,099	53,617
Construction in Progress [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	977	1,309
Buildings [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 24,016	24,016
Property, plant and equipment, Useful life	30 years
Machinery and Equipment [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 124,681	122,485
Machinery and Equipment [Member] \| Minimum [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, Useful life	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, Useful life	10 years
Computer Equipment and Software [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 8,737	$ 8,556
Property, plant and equipment, Useful life	3 years

Property, Plant and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Property Plant And Equipment [Abstract]
Depreciation	$ 7,670	$ 7,651

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accrued Liabilities Current [Abstract]
Employee compensation	$ 2,401	$ 6,472
Other accrued expenses	1,680	1,585
Total	$ 4,081	$ 8,057

Debt - Additional Information (Detail) - Aspen Aerogels Rhode Island, LLC [Member] - Paycheck Protection Program Loan [Member] - USD ($)		9 Months Ended
	May 01, 2020	Sep. 30, 2020
Debt Disclosure [Line Items]
Debt instrument, principal amount	$ 3,685,800
Debt instrument, interest rate	1.00%
Debt instrument, maturity term	2 years
Debt instrument, maturity description		The PPP Loan carries an interest rate of 1% per year and matures two years from the date of the Note. The PPP Loan indebtedness may be forgiven in whole or in part upon application by the Borrower to the PPP Investor. The PPP Investor will determine to what extent the PPP Loan is eligible for forgiveness, subject to SBA guidelines and other regulations, based on the use of loan proceeds for payroll costs, payment of interest on covered mortgage obligations, rent and utility costs over either an eight-week or 24-week period, at the Borrower’s option, following the Borrower’s receipt of the loan proceeds. Upon the Borrower’s application for forgiveness, the SBA will review the Borrower’s eligibility, use of proceeds and other certifications in connection with the application for the PPP Loan. Upon such review, the SBA may approve or deny the Borrower’s loan forgiveness application, in whole or part. As of September 30, 2020, the Borrower had not applied for forgiveness. If the Borrower has not applied for forgiveness within ten months from the end of the 24-week period following receipt of the loan proceeds, the Borrower shall then be required make payments of principal and accrued interest in equal monthly installments over the remaining term of the loan. In addition, the Flexibility Act permits the Borrower and the PPP Investor to mutually agree to extend the term of the PPP Loan to five years from the date of the Note. The Borrower may repay the PPP Loan at any time without penalty.

Debt - Schedule of Long-term Debt (Detail) $ in Thousands	Sep. 30, 2020 USD ($)
Debt Disclosure [Abstract]
Long-term debt, principal	$ 3,686
Current portion of long-term debt	(367)
Debt issuance costs, net of accumulated amortization	(21)
Long-term debt	$ 3,298

Debt - Schedule of Required Principal Payments Remaining on Long-term Debt Outstanding (Detail) $ in Thousands	Sep. 30, 2020 USD ($)
Debt Disclosure [Abstract]
Principal Payments, 2021	$ 1,609
Principal Payments, 2022	2,077
Total principal payments	$ 3,686

Commitments and Contingencies - Additional Information (Detail) - USD ($)					9 Months Ended
	Mar. 03, 2020	Jan. 01, 2020	Jan. 30, 2019	Jan. 01, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Commitments And Contingencies [Line Items]
Prepayment proceeds under customer supply agreement, net						$ 5,000,000
Line of credit facility amount withdrawn							$ 3,123,000
Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member]
Commitments And Contingencies [Line Items]
Maximum increased borrowing amount	$ 20,000,000.0
Interest rate description					the interest rate applicable to borrowings under the revolving credit facility may be based on prime rate or LIBOR, subject to a minimum rate of 4.00% per annum. Prime rate-based rates vary from prime rate plus 0.75% per annum to prime rate plus 2.00% per annum, while LIBOR-based rates vary from LIBOR plus 3.75% per annum to LIBOR plus 4.25% per annum.
Percentage of unused portion of credit facility, monthly fee	0.50%
Revolving Credit Facility [Member]
Commitments And Contingencies [Line Items]
Extended maturity date					Apr. 28, 2021
Line of credit facility amount withdrawn					$ 0
Letters of credit outstanding					1,400,000
Available borrowing capacity					8,100,000
Revolving Credit Facility [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member]
Commitments And Contingencies [Line Items]
Extended maturity date	Apr. 28, 2021
Line of credit facility amount withdrawn					0		3,100,000
Letters of credit outstanding					1,400,000		900,000
Available borrowing capacity					$ 8,100,000
Maximum [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member] \| Prime Rate [Member]
Commitments And Contingencies [Line Items]
Additional interest rate per annum	2.00%
Maximum [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member] \| LIBOR Rate [Member]
Commitments And Contingencies [Line Items]
Additional interest rate per annum	4.25%
Minimum [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member] \| Prime Rate or LIBOR Rate [Member]
Commitments And Contingencies [Line Items]
Additional interest rate per annum	4.00%
Minimum [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member] \| Prime Rate [Member]
Commitments And Contingencies [Line Items]
Additional interest rate per annum	0.75%
Minimum [Member] \| Silicon Valley Bank Credit Facility [Member] \| Loan Agreement [Member] \| LIBOR Rate [Member]
Commitments And Contingencies [Line Items]
Additional interest rate per annum	3.75%
Thermal Barrier Contract [Member] \| OEM [Member]
Commitments And Contingencies [Line Items]
Purchase commitment, description					While the OEM has agreed to purchase its requirement for Barriers at locations to be designated from time to time from the Company, it has no obligation to purchase any minimum quantity of Barriers under the Contract.
Supply and Joint Development Agreement Amended [Member] \| BASF [Member]
Commitments And Contingencies [Line Items]
Supply agreement termination date					Dec. 31, 2027
Prepayment liability			$ 5,000,000.0					$ 5,000,000.0
Credit limit percentage on prepayment balance		50.00%		25.30%
Prepayment proceeds under customer supply agreement, net					$ 10,000,000.0
Credits against amounts invoiced					200,000
Prepayment liability, net of current portion					300,000		$ 300,000
Supply and Joint Development Agreement Amended [Member] \| BASF [Member] \| After December 31, 2022 [Member]
Commitments And Contingencies [Line Items]
Credit limit percentage on prepayment balance			24.70%
Supply and Joint Development Agreement Amended [Member] \| BASF [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Non-interest bearing prepayments, aggregate amount					$ 22,000,000.0

Leases - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Jan. 01, 2019
Leases [Abstract]
Operating lease expiry year	2026
Operating lease liabilities	$ 4,901			$ 6,000
ROU assets	3,702		$ 4,032	4,600
Deferred rent credit de-recognized				$ 1,400
Operating lease cost	1,100	$ 1,200
Cash payments related to operating lease liabilities	$ 1,100	$ 1,100
Operating lease, weighted average remaining lease term	4 years 9 months 18 days
Operating lease, weighted average discount rate, percent	7.70%

Leases - Summary of Maturities of Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2019
Leases [Abstract]
2020 (excluding the nine months ended September 30, 2020)	$ 376
2021	1,331
2022	1,249
2023	1,193
2024	684
Thereafter	1,049
Total lease payments	5,882
Less imputed interest	(981)
Operating lease liabilities	$ 4,901	$ 6,000

Other Long-Term Liabilities - Additional Information (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($)
Other Liabilities Disclosure [Abstract]
Other long-term liabilities	$ 566
Employer payroll tax obligation period	March 27, 2020 to September 30, 2020
Percentage of deferred tax balance	50.00%
Remittance date of deferred tax balance	Dec. 31, 2021
Remaining percentage of deferred tax balance	50.00%
Remittance date of deferred tax balance, remaining percentage	Dec. 31, 2022

Net Loss Per 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, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator:
Net loss	$ (6,753)	$ (5,698)	$ (3,169)	$ (2,289)	$ (5,318)	$ (6,002)	$ (15,620)	$ (13,609)
Denominator:
Weighted average shares outstanding, basic and diluted	26,728,205			24,171,811			26,150,236	24,074,565
Net loss per share, basic and diluted	$ (0.25)			$ (0.09)			$ (0.60)	$ (0.57)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Net Loss Per Share - Summary of Potentially Dilutive Common Shares Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	4,741,419	4,917,726	4,741,419	4,917,726
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	3,918,669	3,683,858	3,918,669	3,683,858
Restricted Common Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	699,559	1,105,415	699,559	1,105,415
Restricted Common Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	123,191	128,453	123,191	128,453

Subsequent Events - Additional Information (Detail)	Nov. 05, 2020 USD ($)
Forecast [Member] \| Maximum [Member] \| B. Riley Securities, Inc. [Member]
Subsequent Event [Line Items]
Common stock aggregate offering price	$ 33,871,250