Aspen Aerogels (ASPN) 10-Q 4 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 03, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
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		28,350,272
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

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 17,219	$ 16,496
Accounts receivable, net of allowances of $199 and $442	20,668	15,698
Inventories	10,847	13,099
Prepaid expenses and other current assets	1,152	1,830
Total current assets	49,886	47,123
Property, plant and equipment, net	45,747	46,739
Operating lease right-of-use assets	4,109	3,478
Other long-term assets	132	84
Total assets	99,874	97,424
Current liabilities:
Accounts payable	6,968	5,351
Accrued expenses	5,306	3,884
Current portion of long-term debt	2,854	1,609
Current portion of prepayment liability	4,562
Deferred revenue	2,061	2,037
Operating lease liabilities	1,152	1,046
Total current liabilities	22,903	13,927
Prepayment liability	5,000	9,555
Long-term debt	817	2,059
Operating lease liabilities long-term	4,077	3,597
Other long-term liabilities	434	434
Total liabilities	33,231	29,572
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock, $0.00001 par value; 5,000,000 shares authorized, no shares issued and outstanding at March 31, 2021 and December 31, 2020
Common stock, $0.00001 par value; 125,000,000 shares authorized, 28,343,535 and 27,821,685 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively		0
Additional paid-in capital	580,852	575,811
Accumulated deficit	(514,209)	(507,959)
Total stockholders’ equity	66,643	67,852
Total liabilities and stockholders’ equity	$ 99,874	$ 97,424

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for accounts receivables	$ 199	$ 442
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	28,343,535	27,821,685
Common stock, shares outstanding	28,343,535	27,821,685

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue:
Total revenue	$ 28,097	$ 28,419
Cost of revenue:
Gross profit	3,956	5,980
Operating expenses:
Research and development	2,442	2,227
Sales and marketing	3,301	3,324
General and administrative	4,388	3,515
Total operating expenses	10,131	9,066
Loss from operations	(6,175)	(3,086)
Interest expense, net	(75)	(83)
Total interest expense, net	(75)	(83)
Net loss	$ (6,250)	$ (3,169)
Net loss per share:
Basic and diluted	$ (0.22)	$ (0.13)
Weighted-average common shares outstanding:
Basic and diluted	27,983,470	25,194,292
Product [Member]
Revenue:
Total revenue	$ 28,056	$ 28,307
Cost of revenue:
Cost of revenue	24,129	22,399
Research Services [Member]
Revenue:
Total revenue	41	112
Cost of revenue:
Cost of revenue	$ 12	$ 40

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Underwritten Public Offering [Member]	At The Market Offering [Member]	Common Stock 0.00001 Par Value [Member]	Common Stock 0.00001 Par Value [Member]Underwritten Public Offering [Member]	Common Stock 0.00001 Par Value [Member]At The Market Offering [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Underwritten Public Offering [Member]	Additional Paid-in Capital [Member]At The Market Offering [Member]	Accumulated Deficit [Member]
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 offering, net		$ 14,751						$ 14,751
Proceeds from offering, net, 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, 2020	67,852						575,811			(507,959)
Beginning balance, shares at Dec. 31, 2020				27,821,685
Net loss	(6,250)									(6,250)
Stock compensation expense	976						976
Vesting of restricted stock units	(2,613)						(2,613)
Vesting of restricted stock units, shares				246,737
Proceeds from employee stock option exercises	463						463
Proceeds from employee stock option exercises, shares				48,056
Proceeds from offering, net			$ 6,215						$ 6,215
Proceeds from offering, net, shares						305,182
Forfeiture of performance-based restricted stock, shares				(78,125)
Ending balance at Mar. 31, 2021	$ 66,643						$ 580,852			$ (514,209)
Ending balance, shares at Mar. 31, 2021				28,343,535

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
At The Market Offering [Member]
Commissions and fees	$ 193
Issuance costs	$ 17
Underwritten Public Offering [Member]
Issuance costs		$ 285
Underwriting discounts and commissions		$ 1,093

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net loss	$ (6,250,000)	$ (3,169,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2,638,000	2,563,000
Amortization of debt issuance costs	3,000
Provision for bad debt	(95,000)	0
Stock-compensation expense	976,000	992,000
Reduction in the carrying amount of operating lease right-of-use assets	257,000	243,000
Changes in operating assets and liabilities:
Accounts receivable	(4,875,000)	11,799,000
Inventories	2,252,000	(4,664,000)
Prepaid expenses and other assets	630,000	181,000
Accounts payable	1,432,000	(3,732,000)
Accrued expenses	1,422,000	(4,441,000)
Deferred revenue	31,000	(851,000)
Operating lease liabilities	(293,000)	(274,000)
Net cash used in operating activities	(1,872,000)	(1,353,000)
Cash flows from investing activities:
Capital expenditures	(1,470,000)	(927,000)
Net cash used in investing activities	(1,470,000)	(927,000)
Cash flows from financing activities:
Repayments of borrowings under line of credit, net		(3,123,000)
Proceeds from employee stock option exercises	463,000
Payments made for employee restricted stock tax withholdings	(2,613,000)	(1,195,000)
Net cash provided by financing activities	4,065,000	10,433,000
Net increase in cash	723,000	8,153,000
Cash and cash equivalents at beginning of period	16,496,000	3,633,000
Cash and cash equivalents at end of period	17,219,000	11,786,000
Supplemental disclosures of cash flow information:
Interest paid	65,000	84,000
Income taxes paid	0	0
Supplemental disclosures of non-cash activities:
Right-of-use assets obtained in exchange for new operating lease liabilities	888,000	152,000
Changes in accrued capital expenditures	176,000	(147,000)
Underwritten Public Offering [Member]
Cash flows from financing activities:
Proceeds from offering, net		15,036,000
Issuance costs		$ (285,000)
At The Market Offering [Member]
Cash flows from financing activities:
Proceeds from offering, net	6,232,000
Issuance costs	$ (17,000)

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Underwritten Public Offering [Member]
Underwriting discounts and commissions, net		$ 1,093
At The Market Offering [Member]
Commissions and fees net	$ 193

Description of Business and Bas

Description of Business and Basis of Presentation	3 Months Ended
	Mar. 31, 2021
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 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 three months ended March 31, 2021, the Company incurred a net loss of $6.3 million, used $1.9 million of cash in operations, used $1.5 million of cash for capital expenditures and received net proceeds of $6.2 million through an at-the-market offering of the Company’s common stock. At March 31, 2021, the Company had cash and cash equivalents of $17.2 million, total debt of $3.7 million, a $4.6 million current prepayment liability (see note 9), and no outstanding borrowings under its revolving line of credit (see note 7). After giving effect to $1.5 million of outstanding letters of credit, t he amount available to the Company at March 31, 2021 under the revolving line of credit was $13.1 million. The Company is increasing investment in the research and development of next-generation aerogel products and manufacturing process technologies. The Company is continuing to develop aerogel products and technologies for the electric vehicle market. The Company believes that the commercial potential for the Company’s technology in the electric vehicle market is significant. Accordingly, the Company plans to continue to hire additional personnel, incur additional operating expenses, and incur capital expenditures to expand silica aerogel manufacturing capacity, build an automated thermal barrier fabrication operation, enhance research and development laboratory facilities and equipment, and construct a battery materials facility, 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. 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, 2020 (the Annual Report), filed with the U.S. Securities and Exchange Commission on March 12, 2021. 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 March 31, 2021 and the results of its operations and stockholders’ equity for the three months ended March 31, 2021 and 2020 and the cash flows for the three 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 months ended March 31, 2021 are not necessarily indicative of the results to be expected for the year ending December 31, 2021 or any other period. In addition, the Company is uncertain of the continued duration and severity of the COVID-19 pandemic and the impact it will have on the Company’s results of operations for the year ending December 31, 2021 or any other period.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
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 three months ended March 31, 2021, the Company recorded a reduction for estimated customer uncollectible accounts receivable of $0.1 million and had collections of $0.1 million of previously reserved customer accounts receivables. The Company did not record a charge for uncollectible accounts receivable during the three months ended March 31, 2020. 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 The Company accounts for its leases in accordance with Accounting Standards Update (ASU) 2016-02 (Topic 842). See note 10 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 three months ended March 31, 2021, the Company granted 61,370 restricted common stock units (RSUs) with a grant date fair value of $1.5 million and non-qualified stock options (NSOs) to purchase 199,324 shares of common stock with a grant date fair value of $2.6 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 Stock-based compensation is included in cost of revenue or operating expenses, as applicable, and consists of the following: Three Months Ended March 31, 2021 2020 (In thousands) Cost of product revenue $ 112 $ 319 Research and development expenses 189 146 Sales and marketing expenses 168 171 General and administrative expenses 507 356 Total stock-based compensation $ 976 $ 992 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 556,433 shares to 8,531,413 shares effective January 1, 2021. As of March 31, 2021, 4,130,907 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 March 31, 2021, 80,658 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 March 31, 2021, the Company has either reserved in connection with statutory tax withholdings or issued a total of 3,123,562 shares under the 2014 Equity Plan. As of March 31, 2021, there were 1,196,286 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 presently 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 March 31, 2021 2020 (In thousands) Revenue: U.S. $ 12,755 $ 13,673 International 15,342 14,746 Total $ 28,097 $ 28,419 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. The Company did not record any warranty expense during the three months ended March 31, 2021 and 2020. 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, 2020 The Company has not implemented any accounting standards that had a material impact on its consolidated financial statements during the three months ended March 31, 2021. 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 Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2021
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, 2020 and did not enter into any contracts during the three months ended March 31, 2021 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 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 March 31, 2021 and December 31, 2020. Subsea Projects The Company manufactures and sells subsea products that are designed for pipe-in-pipe applications in subsea oil production and are typically at a point in time when transfer of control of the products is passed to the customer, or , 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 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 March 31, 2021 2020 U.S. International Total U.S. International Total (In thousands) Geographical region Asia $ — $ 5,588 $ 5,588 $ — $ 10,104 $ 10,104 Canada — 964 964 — 455 455 Europe — 7,246 7,246 — 3,137 3,137 Latin America — 1,544 1,544 — 1,050 1,050 U.S. 12,755 — 12,755 13,673 — 13,673 Total revenue $ 12,755 $ 15,342 $ 28,097 $ 13,673 $ 14,746 $ 28,419 Source of revenue Product revenue $ 12,714 $ 14,935 $ 27,649 $ 12,453 $ 13,633 $ 26,086 Subsea projects — 407 407 1,108 1,113 2,221 Research services 41 41 112 — 112 Total revenue $ 12,755 $ 15,342 $ 28,097 $ 13,673 $ 14,746 $ 28,419 Contract Balances The following table presents changes in the Company’s contract assets and contract liabilities during the three months ended March 31, 2021: Balance at December 31, 2020 Additions Deductions Balance at March 31, 2021 (In thousands) Contract assets Subsea projects $ 1,370 $ 720 $ (1,045 ) $ 1,045 Research services 67 41 (83 ) 25 Total contract assets $ 1,437 $ 761 $ (1,128 ) $ 1,070 Contract liabilities Deferred revenue Product revenue $ 1,859 $ 2,030 $ (2,319 ) $ 1,570 Subsea projects 178 $ 491 $ (178 ) 491 Prepayment liability 9,555 7 — 9,562 Total contract liabilities $ 11,592 $ 2,528 $ (2,497 ) $ 11,623 During the three months ended March 31, 2021, the Company recognized $1.5 million of revenue that was included in deferred revenue at December 31, 2020. 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.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2021
Inventory Disclosure [Abstract]
Inventories	(4) Inventories Inventories consist of the following: March 31, December 31, 2021 2020 (In thousands) Raw materials $ 4,090 $ 4,068 Finished goods 6,757 9,031 Total $ 10,847 $ 13,099

Property, Plant and Equipment,

Property, Plant and Equipment, Net	3 Months Ended
	Mar. 31, 2021
Property Plant And Equipment [Abstract]
Property, Plant and Equipment, Net	(5) Property, Plant and Equipment, Net Property, plant and equipment consist of the following: March 31, December 31, Useful 2021 2020 life (In thousands) Construction in progress $ 1,784 $ 1,906 — Buildings 24,016 24,016 30 years Machinery and equipment 126,284 124,807 3-10 years Computer equipment and software 8,885 8,850 3 years Total 160,969 159,579 Accumulated depreciation (115,222 ) (112,840 ) Property, plant and equipment, net $ 45,747 $ 46,739 Depreciation expense was $2.6 million for the three months ended March 31, 2021 and 2020. Construction in progress totaled $1.8 million and $1.9 million at March 31, 2021 and December 31, 2020, respectively, associated with the Company’s East Providence, Rhode Island facility.

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Accrued Expenses	(6) Accrued Expenses Accrued expenses consist of the following: March 31, December 31, 2021 2020 (In thousands) Employee compensation $ 3,817 $ 2,587 Other accrued expenses 1,489 1,297 Total $ 5,306 $ 3,884

Revolving Line of Credit

Revolving Line of Credit	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Revolving Line of Credit	(7) 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 12, 2021, the Loan Agreement was amended and restated to extend the maturity date of the revolving credit facility to April 28, 2022 and to establish certain minimum Adjusted EBITDA levels and minimum Adjusted Quick Ratio covenants, as defined. 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. The interest rate applicable to borrowings under the revolving credit facility is based on prime rate, 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. In addition, the Company is required to pay a monthly unused revolving line facility fee of 0.50% 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 and a minimum Adjusted Quick Ratio covenant, as defined. At March 31, 2021, 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 ma At March 31, 2021 and December 31, 2020, the Company had no amounts drawn from the revolving credit facility. The Company has provided 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 $1.5 million and $1.4 million at March 31, 2021 and December 31, 2020, respectively, which reduce the funds otherwise available to the Company under the facility. At March 31, 2021, the amount available to the Company under the revolving credit facility was $13.1 million after giving effect to the $1.5 million of outstanding letters of credit.

Debt

Debt	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Debt	(8) 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 $3.7 million (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 March 31, 2021, 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 will 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 failed 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 in part, the Borrower will be required to make payments of principal and accrued interest in equal monthly installments over the remaining term of the loan for the 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: March 31, December 31, 2021 2020 (In thousands) Long-term debt, principal $ 3,686 $ 3,686 Current portion of long-term debt (2,854 ) (1,609 ) Debt issuance costs, net of accumulated amortization (15 ) (18 ) Long-term debt $ 817 $ 2,059 The schedule of required principal payments remaining on long-term debt outstanding as of March 31, 2021 is as follows: Year Principal Payments (In thousands) 2021 (excluding the three months ended March 31, 2021) 1,609 2022 2,077 Total principal payments $ 3,686

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	(9) Commitments and Contingencies Cloud Computing Agreement The Company is party to a cloud computing agreement that is a service contract for enterprise resource planning software. The agreement has a three-year 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 are 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 beginning in 2022. 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 As of March 31, 2021, the Company had received $10.0 million in prepayments from BASF and applied approximately $0.2 million of credits against amounts invoiced. The prepayment liability consists of the following: March 31, December 31, 2021 2020 (In thousands) Prepayment liability $ 9,832 $ 9,845 Current portion of prepayment liability (4,562 ) — Prepayment liability included within deferred revenue (270 ) (290 ) Prepayment liability, long-term $ 5,000 $ 9,555 The amounts and terms of additional prepayment installments, if any, are subject to negotiation between the Company and BASF. 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. 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

Leases	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Leases	(10) 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. 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. Maturities of operating lease liabilities at March 31, 2021 are as follows: Year Operating Leases (In thousands) 2021 (excluding the three months ended March 31, 2021) 1,121 2022 1,440 2023 1,389 2024 885 2025 723 Thereafter 584 Total lease payments 6,142 Less imputed interest (913 ) Total lease liabilities $ 5,229 The Company incurred operating lease costs of $0.4 million and $0.3 million during the three months ended March 31, 2021 and 2020, respectively. Cash payments related to operating lease liabilities were $0.4 million during both the three months ended March 31, 2021 and 2020. At March 31, 2021, the weighted average remaining lease term for operating leases was 4.6 years. At March 31, 2021, the weighted average discount rate for operating leases was 7.3%. As of March 31, 2021, the Company has additional operating equipment leases that will commence during 2021 with total lease payments of $0.2 million and a weighted average lease term of 4.0 years.

CARES Act Payroll Tax Deferral

CARES Act Payroll Tax Deferral	3 Months Ended
	Mar. 31, 2021
Other Liabilities Disclosure [Abstract]
CARES Act Payroll Tax Deferral	(11) CARES Act Payroll Tax Deferral The Company elected to defer approximately $0.9 million of its employer payroll tax obligation for the period from March 27, 2020 to December 31, 2020 pursuant to the provisions of the CARES Act. The Company is required to remit 50 percent of the deferred tax balance on or before December 31, 2021 and the remaining 50 percent on or before December 31, 2022. Other long-term liabilities consist of the following: March 31, December 31, 2021 2020 (In thousands) Deferred employer payroll tax obligation $ 870 $ 870 Current portion of deferred payroll tax obligation (436 ) (436 ) Other long-term liabilities $ 434 $ 434

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share	(12) Net Loss Per Share The computation of basic and diluted net loss per share consists of the following: Three Months Ended March 31, 2021 2020 (In thousands, except share and per share data) Numerator: Net loss $ (6,250 ) $ (3,169 ) Denominator: Weighted average shares outstanding, basic and diluted 27,983,470 25,194,292 Net loss per share, basic and diluted $ (0.22 ) $ (0.13 ) 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 Months Ended March 31, 2021 2020 Common stock options 3,846,738 4,143,821 Restricted common stock units 364,828 720,969 Restricted common stock awards 45,066 128,453 Total 4,256,632 4,993,243 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

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	(13) 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.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	(14) Subsequent Events The Company has evaluated subsequent events through May 4, 2021, the date of issuance of the consolidated financial statements for the three months ended March 31, 2021

Description of Business and B_2

Description of Business and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Nature of Business	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 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	Liquidity During the three months ended March 31, 2021, the Company incurred a net loss of $6.3 million, used $1.9 million of cash in operations, used $1.5 million of cash for capital expenditures and received net proceeds of $6.2 million through an at-the-market offering of the Company’s common stock. At March 31, 2021, the Company had cash and cash equivalents of $17.2 million, total debt of $3.7 million, a $4.6 million current prepayment liability (see note 9), and no outstanding borrowings under its revolving line of credit (see note 7). After giving effect to $1.5 million of outstanding letters of credit, t he amount available to the Company at March 31, 2021 under the revolving line of credit was $13.1 million. The Company is increasing investment in the research and development of next-generation aerogel products and manufacturing process technologies. The Company is continuing to develop aerogel products and technologies for the electric vehicle market. The Company believes that the commercial potential for the Company’s technology in the electric vehicle market is significant. Accordingly, the Company plans to continue to hire additional personnel, incur additional operating expenses, and incur capital expenditures to expand silica aerogel manufacturing capacity, build an automated thermal barrier fabrication operation, enhance research and development laboratory facilities and equipment, and construct a battery materials facility, 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.
Unaudited Interim Financial Information	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, 2020 (the Annual Report), filed with the U.S. Securities and Exchange Commission on March 12, 2021. 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 March 31, 2021 and the results of its operations and stockholders’ equity for the three months ended March 31, 2021 and 2020 and the cash flows for the three 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 months ended March 31, 2021 are not necessarily indicative of the results to be expected for the year ending December 31, 2021 or any other period. In addition, the Company is uncertain of the continued duration and severity of the COVID-19 pandemic and the impact it will have on the Company’s results of operations for the year ending December 31, 2021 or any other period.
Principles of Consolidation	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	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 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	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 three months ended March 31, 2021, the Company recorded a reduction for estimated customer uncollectible accounts receivable of $0.1 million and had collections of $0.1 million of previously reserved customer accounts receivables. The Company did not record a charge for uncollectible accounts receivable during the three months ended March 31, 2020.
Revenue Recognition	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	Leases The Company accounts for its leases in accordance with Accounting Standards Update (ASU) 2016-02 (Topic 842). See note 10 for further details.
Stock-based Compensation	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 three months ended March 31, 2021, the Company granted 61,370 restricted common stock units (RSUs) with a grant date fair value of $1.5 million and non-qualified stock options (NSOs) to purchase 199,324 shares of common stock with a grant date fair value of $2.6 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 Stock-based compensation is included in cost of revenue or operating expenses, as applicable, and consists of the following: Three Months Ended March 31, 2021 2020 (In thousands) Cost of product revenue $ 112 $ 319 Research and development expenses 189 146 Sales and marketing expenses 168 171 General and administrative expenses 507 356 Total stock-based compensation $ 976 $ 992 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 556,433 shares to 8,531,413 shares effective January 1, 2021. As of March 31, 2021, 4,130,907 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 March 31, 2021, 80,658 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 March 31, 2021, the Company has either reserved in connection with statutory tax withholdings or issued a total of 3,123,562 shares under the 2014 Equity Plan. As of March 31, 2021, there were 1,196,286 shares of common stock available for future grant under the 2014 Equity Plan.
Net Loss per Share	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	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 presently 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 March 31, 2021 2020 (In thousands) Revenue: U.S. $ 12,755 $ 13,673 International 15,342 14,746 Total $ 28,097 $ 28,419
Warranty	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. The Company did not record any warranty expense during the three months ended March 31, 2021 and 2020.
Recently Issued Accounting Standards	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, 2020 The Company has not implemented any accounting standards that had a material impact on its consolidated financial statements during the three months ended March 31, 2021. 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 Polici_2

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
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 March 31, 2021 2020 (In thousands) Cost of product revenue $ 112 $ 319 Research and development expenses 189 146 Sales and marketing expenses 168 171 General and administrative expenses 507 356 Total stock-based compensation $ 976 $ 992
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 March 31, 2021 2020 (In thousands) Revenue: U.S. $ 12,755 $ 13,673 International 15,342 14,746 Total $ 28,097 $ 28,419

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2021
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 March 31, 2021 2020 U.S. International Total U.S. International Total (In thousands) Geographical region Asia $ — $ 5,588 $ 5,588 $ — $ 10,104 $ 10,104 Canada — 964 964 — 455 455 Europe — 7,246 7,246 — 3,137 3,137 Latin America — 1,544 1,544 — 1,050 1,050 U.S. 12,755 — 12,755 13,673 — 13,673 Total revenue $ 12,755 $ 15,342 $ 28,097 $ 13,673 $ 14,746 $ 28,419 Source of revenue Product revenue $ 12,714 $ 14,935 $ 27,649 $ 12,453 $ 13,633 $ 26,086 Subsea projects — 407 407 1,108 1,113 2,221 Research services 41 41 112 — 112 Total revenue $ 12,755 $ 15,342 $ 28,097 $ 13,673 $ 14,746 $ 28,419
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 three months ended March 31, 2021: Balance at December 31, 2020 Additions Deductions Balance at March 31, 2021 (In thousands) Contract assets Subsea projects $ 1,370 $ 720 $ (1,045 ) $ 1,045 Research services 67 41 (83 ) 25 Total contract assets $ 1,437 $ 761 $ (1,128 ) $ 1,070 Contract liabilities Deferred revenue Product revenue $ 1,859 $ 2,030 $ (2,319 ) $ 1,570 Subsea projects 178 $ 491 $ (178 ) 491 Prepayment liability 9,555 7 — 9,562 Total contract liabilities $ 11,592 $ 2,528 $ (2,497 ) $ 11,623

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2021
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consist of the following: March 31, December 31, 2021 2020 (In thousands) Raw materials $ 4,090 $ 4,068 Finished goods 6,757 9,031 Total $ 10,847 $ 13,099

Property, Plant and Equipment_2

Property, Plant and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2021
Property Plant And Equipment [Abstract]
Summary of Property, Plant and Equipment	Property, plant and equipment consist of the following: March 31, December 31, Useful 2021 2020 life (In thousands) Construction in progress $ 1,784 $ 1,906 — Buildings 24,016 24,016 30 years Machinery and equipment 126,284 124,807 3-10 years Computer equipment and software 8,885 8,850 3 years Total 160,969 159,579 Accumulated depreciation (115,222 ) (112,840 ) Property, plant and equipment, net $ 45,747 $ 46,739

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following: March 31, December 31, 2021 2020 (In thousands) Employee compensation $ 3,817 $ 2,587 Other accrued expenses 1,489 1,297 Total $ 5,306 $ 3,884

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Long-term debt consists of the following: March 31, December 31, 2021 2020 (In thousands) Long-term debt, principal $ 3,686 $ 3,686 Current portion of long-term debt (2,854 ) (1,609 ) Debt issuance costs, net of accumulated amortization (15 ) (18 ) Long-term debt $ 817 $ 2,059
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 March 31, 2021 is as follows: Year Principal Payments (In thousands) 2021 (excluding the three months ended March 31, 2021) 1,609 2022 2,077 Total principal payments $ 3,686

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Schedule of Prepayment Liability	The prepayment liability consists of the following: March 31, December 31, 2021 2020 (In thousands) Prepayment liability $ 9,832 $ 9,845 Current portion of prepayment liability (4,562 ) — Prepayment liability included within deferred revenue (270 ) (290 ) Prepayment liability, long-term $ 5,000 $ 9,555

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Summary of Maturities of Operating Lease Liabilities	Maturities of operating lease liabilities at March 31, 2021 are as follows: Year Operating Leases (In thousands) 2021 (excluding the three months ended March 31, 2021) 1,121 2022 1,440 2023 1,389 2024 885 2025 723 Thereafter 584 Total lease payments 6,142 Less imputed interest (913 ) Total lease liabilities $ 5,229

CARES Act Payroll Tax Deferral

CARES Act Payroll Tax Deferral (Tables)	3 Months Ended
	Mar. 31, 2021
Other Liabilities Disclosure [Abstract]
Summary of Other Long-term Liabilities	Other long-term liabilities consist of the following: March 31, December 31, 2021 2020 (In thousands) Deferred employer payroll tax obligation $ 870 $ 870 Current portion of deferred payroll tax obligation (436 ) (436 ) Other long-term liabilities $ 434 $ 434

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
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 March 31, 2021 2020 (In thousands, except share and per share data) Numerator: Net loss $ (6,250 ) $ (3,169 ) Denominator: Weighted average shares outstanding, basic and diluted 27,983,470 25,194,292 Net loss per share, basic and diluted $ (0.22 ) $ (0.13 )
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 Months Ended March 31, 2021 2020 Common stock options 3,846,738 4,143,821 Restricted common stock units 364,828 720,969 Restricted common stock awards 45,066 128,453 Total 4,256,632 4,993,243

Description of Business and B_3

Description of Business and Basis of Presentation - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021USD ($)Subsidiary	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Basis Of Presentation [Line Items]
Number of Subsidiaries | Subsidiary	3
Net loss incurred	$ 6,250,000	$ 3,169,000
Cash used in operations	1,872,000	$ 1,353,000
Cash for capital expenditures	1,500,000
Cash and cash equivalents	17,219,000		$ 16,496,000
Total debt	3,700,000
Current portion of prepayment liability	4,562,000
At The Market Offering [Member]
Basis Of Presentation [Line Items]
Proceeds from offering, net	6,232,000
Revolving Credit Facility [Member]
Basis Of Presentation [Line Items]
Outstanding borrowings under revolving line of credit	0
Letters of credit outstanding	1,500,000
Amount available under revolving line of credit	$ 13,100,000
Existing maturity date	Apr. 28, 2022

Significant Accounting Polici_3

Significant Accounting Policies - Additional Information (Detail)	Jan. 01, 2021shares	Mar. 31, 2021USD ($)Segmentshares	Mar. 31, 2020USD ($)
Summary Of Significant Accounting Policies [Line Items]
Reduction/Charge for uncollectible accounts receivable | $		$ (95,000)	$ 0
Collections of accounts receivable | $		$ 100,000
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	556,433
Increased number of shares authorized for grant	8,531,413
Shares reserved for issuance		4,130,907
Number of shares either issued or reserved in connection with statutory tax withholdings		3,123,562
Increased number of shares available for grant		1,196,286
2014 Equity Plan [Member] | Non-Qualified Stock Options [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		199,324
Stock-based awards granted to purchase common stock, grant date fair value | $		$ 2,600,000
Stock-based award vesting period		3 years
2014 Equity Plan [Member] | Restricted Stock Units [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock-based awards granted to purchase common stock		61,370
Stock-based awards granted to purchase common stock, grant date fair value | $		$ 1,500,000
Stock-based award vesting period		3 years
2001 Equity Incentive Plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares reserved for issuance		80,658

Significant Accounting Polici_4

Significant Accounting Policies - Summary of Stock Based Compensation Included in Cost of Revenue or Operating Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 976	$ 992
Cost of Product Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	112	319
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	189	146
Sales and Marketing Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	168	171
General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 507	$ 356

Significant Accounting Polici_5

Significant Accounting Policies - Schedule of Revenues, Based on Shipment Destination or Research Services Location (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Revenue	$ 28,097	$ 28,419
U.S. [Member]
Segment Reporting Information [Line Items]
Revenue	12,755	13,673
International [Member]
Segment Reporting Information [Line Items]
Revenue	$ 15,342	$ 14,746

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)Agreement	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Revenue Recognition [Line Items]
Revenue	$ 28,097	$ 28,419
Deferred revenue, revenue recognized	1,500
Maximum [Member]
Revenue Recognition [Line Items]
Sales return reserves	$ 100		$ 100
Product Revenue [Member]
Revenue Recognition [Line Items]
Number of performance obligations | Agreement	1
Revenue	$ 27,649	26,086
Subsea Projects [Member]
Revenue Recognition [Line Items]
Revenue	$ 407	2,221
Research Services [Member]
Revenue Recognition [Line Items]
Number of performance obligations | Agreement	1
Revenue	$ 41	$ 112

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Summary of Revenue Disaggregated by Geographical Region and Source of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Total revenue	$ 28,097	$ 28,419
Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	27,649	26,086
Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	407	2,221
Research Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	41	112
Asia [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	5,588	10,104
Canada [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	964	455
Europe [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	7,246	3,137
Latin America [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	1,544	1,050
U.S. [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	12,755	13,673
U.S. [Member] | Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	12,714	12,453
U.S. [Member] | Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		1,108
U.S. [Member] | Research Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	41	112
International [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	15,342	14,746
International [Member] | Product Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	14,935	13,633
International [Member] | Subsea Projects [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 407	$ 1,113

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Summary of Changes in Contract Assets and Contract Liabilities (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Contract assets
Beginning Balance	$ 1,437
Additions	761
Deductions	(1,128)
Ending Balance	1,070
Contract liabilities
Beginning Balance	11,592
Additions	2,528
Deductions	(2,497)
Ending Balance	11,623
Subsea Projects [Member]
Contract assets
Beginning Balance	1,370
Additions	720
Deductions	(1,045)
Ending Balance	1,045
Contract liabilities
Beginning Balance	178
Additions	491
Deductions	(178)
Ending Balance	491
Research Services [Member]
Contract assets
Beginning Balance	67
Additions	41
Deductions	(83)
Ending Balance	25
Product Revenue [Member]
Contract liabilities
Beginning Balance	1,859
Additions	2,030
Deductions	(2,319)
Ending Balance	1,570
Prepayment Liability [Member]
Contract liabilities
Beginning Balance	9,555
Additions	7
Ending Balance	$ 9,562

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 4,090	$ 4,068
Finished goods	6,757	9,031
Total	$ 10,847	$ 13,099

Property, Plant and Equipment_3

Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 160,969	$ 159,579
Accumulated depreciation	(115,222)	(112,840)
Property, plant and equipment, net	45,747	46,739
Construction in Progress [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,784	1,906
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	$ 126,284	124,807
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	$ 8,885	$ 8,850
Property, plant and equipment, Useful life	3 years

Property, Plant and Equipment_4

Property, Plant and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property Plant and Equipment [Line Items]
Depreciation	$ 2,638	$ 2,563
Property, plant and equipment, gross	160,969		$ 159,579
Construction in Progress [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,784		1,906
Rhode Island [Member] | Construction in Progress [Member]
Property Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 1,800		$ 1,900

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued Liabilities Current [Abstract]
Employee compensation	$ 3,817	$ 2,587
Other accrued expenses	1,489	1,297
Total	$ 5,306	$ 3,884

Revolving Line of Credit - Addi

Revolving Line of Credit - Additional Information (Detail) - USD ($)	Mar. 12, 2021	Mar. 31, 2021	Dec. 31, 2020
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Extended maturity date		Apr. 28, 2022
Line of credit facility amount withdrawn		$ 0
Letters of credit outstanding		1,500,000
Available borrowing capacity		13,100,000
Silicon Valley Bank Credit Facility [Member] | Loan Agreement [Member]
Line of Credit Facility [Line Items]
Maximum increased borrowing amount		$ 20,000,000
Interest rate description		The interest rate applicable to borrowings under the revolving credit facility is based on prime rate, 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.
Percentage of unused portion of facility, monthly fee		0.50%
Silicon Valley Bank Credit Facility [Member] | Loan Agreement [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Revolving credit facility, interest rate		4.00%
Silicon Valley Bank Credit Facility [Member] | Loan Agreement [Member] | Prime Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Additional interest rate per annum		0.75%
Silicon Valley Bank Credit Facility [Member] | Loan Agreement [Member] | Prime Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Additional interest rate per annum		2.00%
Silicon Valley Bank Credit Facility [Member] | Loan Agreement [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Extended maturity date	Apr. 28, 2022
Line of credit facility amount withdrawn		$ 0	$ 0
Letters of credit outstanding		1,500,000	$ 1,400,000
Available borrowing capacity		$ 13,100,000

Debt - Additional Information (

Debt - Additional Information (Detail) - Aspen Aerogels Rhode Island, LLC [Member] - Paycheck Protection Program Loan [Member] - USD ($) $ in Millions	May 01, 2020	Mar. 31, 2021
Debt Disclosure [Line Items]
Debt instrument, principal amount	$ 3.7
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 March 31, 2021, 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 will 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 De

Debt - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Long-term debt, principal	$ 3,686	$ 3,686
Current portion of long-term debt	(2,854)	(1,609)
Debt issuance costs, net of accumulated amortization	(15)	(18)
Long-term debt	$ 817	$ 2,059

Debt - Schedule of Required Pri

Debt - Schedule of Required Principal Payments Remaining on Long-term Debt Outstanding (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
2021 (excluding the three months ended March 31, 2021)	$ 1,609
Principal Payments, 2022	2,077
Total principal payments	$ 3,686	$ 3,686

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	Jan. 01, 2020	Jan. 30, 2019	Jan. 01, 2019	Mar. 31, 2021	Dec. 31, 2018
Cloud Computing Agreement [Member] | Enterprise Resource Planning Software [Member]
Commitments And Contingencies [Line Items]
Debt instrument, maturity term				3 years
Cloud Computing Agreement [Member] | Enterprise Resource Planning Software [Member] | Maximum [Member]
Commitments And Contingencies [Line Items]
Capitalized costs related to implementation of agreement				$ 100,000
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			$ 5,000,000
Credit limit percentage on prepayment balance	50.00%		25.30%
Prepayment proceeds under customer supply agreement, net				$ 10,000,000
Credits against amounts invoiced				200,000
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

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Prepayment Liability (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Prepayment Liability [Abstract]
Prepayment liability	$ 9,832	$ 9,845
Current portion of prepayment liability	(4,562)
Prepayment liability included within deferred revenue	(270)	(290)
Prepayment liability, long-term	$ 5,000	$ 9,555

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Operating lease expiry year	2026
Operating lease cost	$ 0.4	$ 0.3
Cash payments related to operating lease liabilities	$ 0.4	$ 0.4
Operating lease, weighted average remaining lease term	4 years 7 months 6 days
Operating lease, weighted average discount rate, percent	7.30%
Operating lease liability payments not yet commenced	$ 0.2
Operating lease, weighted average lease not yet commenced, term	4 years

Leases - Summary of Maturities

Leases - Summary of Maturities of Operating Lease Liabilities (Detail) $ in Thousands	Mar. 31, 2021USD ($)
Leases [Abstract]
2021 (excluding the three months ended March 31, 2021)	$ 1,121
2022	1,440
2023	1,389
2024	885
2025	723
Thereafter	584
Total lease payments	6,142
Less imputed interest	(913)
Total lease liabilities	$ 5,229

CARES Act Payroll Tax Deferra_2

CARES Act Payroll Tax Deferral - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Deferred employer payroll tax obligation	$ 870	$ 870
Employer payroll tax obligation period	March 27, 2020 to December 31, 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

CARES Act Payroll Tax Deferra_3

CARES Act Payroll Tax Deferral - Summary of Other Long-term Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Deferred employer payroll tax obligation	$ 870	$ 870
Current portion of deferred payroll tax obligation	(436)	(436)
Other long-term liabilities	$ 434	$ 434

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (6,250)	$ (3,169)
Denominator:
Weighted average shares outstanding, basic and diluted	27,983,470	25,194,292
Net loss per share, basic and diluted	$ (0.22)	$ (0.13)

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Potentially Dilutive Common Shares Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	4,256,632	4,993,243
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	3,846,738	4,143,821
Restricted Common Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	364,828	720,969
Restricted Common Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive Securities	45,066	128,453