Personalis (PSNL) 10-Q 4 Aug 21 2021 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Jul. 30, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Entity Registrant Name	Personalis, Inc.
Entity Central Index Key	0001527753
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		44,412,483
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-38943
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	27-5411038
Entity Address, Address Line One	1330 O’Brien Drive
Entity Address, City or Town	Menlo Park
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94025
City Area Code	650
Local Phone Number	752-1300
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
Title of 12(b) Security	Common Stock, par value $0.0001
Trading Symbol	PSNL
Security Exchange Name	NASDAQ

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 70,080	$ 68,525
Short-term investments	258,827	134,765
Accounts receivable, net	9,278	6,349
Inventory and other deferred costs	7,321	5,639
Prepaid expenses and other current assets	8,803	5,441
Total current assets	354,309	220,719
Property and equipment, net	14,258	11,834
Operating lease right-of-use assets	11,126	10,271
Other long-term assets	3,647	2,018
Total assets	383,340	244,842
Current liabilities
Accounts payable	8,919	8,301
Accrued and other current liabilities	13,708	11,301
Contract liabilities	11,460	21,034
Total current liabilities	34,087	40,636
Long-term operating lease liabilities	8,518	8,541
Other long-term liabilities	1,988	720
Total liabilities	44,593	49,897
Commitments and Contingencies (Note 9)
Stockholders’ equity
Common stock, $0.0001 par value — 200,000,000 shares authorized; 44,209,968 and 39,105,548 shares issued and outstanding at June 30, 2021 and December 31, 2020, respectively	4	4
Additional paid-in capital	547,951	376,788
Accumulated other comprehensive income (loss)	18	22
Accumulated deficit	(209,226)	(181,869)
Total stockholders’ equity	338,747	194,945
Total liabilities and stockholders’ equity	$ 383,340	$ 244,842

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - $ / shares	Jun. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares, issued	44,209,968	39,105,548
Common stock, shares, outstanding	44,209,968	39,105,548

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenue	$ 21,670	$ 19,495	$ 42,551	$ 38,656
Costs and expenses
Cost of revenue	13,502	14,823	26,956	29,945
Research and development	11,687	6,465	21,183	12,855
Selling, general and administrative	11,428	7,705	21,849	14,979
Total costs and expenses	36,617	28,993	69,988	57,779
Loss from operations	(14,947)	(9,498)	(27,437)	(19,123)
Interest income	103	246	198	756
Interest expense	(65)		(65)	(2)
Other income (expense), net	(36)	1	(48)	9
Loss before income taxes	(14,945)	(9,251)	(27,352)	(18,360)
Provision for income taxes	8	4	5	34
Net loss	$ (14,953)	$ (9,255)	$ (27,357)	$ (18,394)
Net loss per share, basic and diluted	$ (0.34)	$ (0.29)	$ (0.63)	$ (0.58)
Weighted-average shares outstanding, basic and diluted	43,960,794	31,731,628	43,113,195	31,538,329

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (14,953)	$ (9,255)	$ (27,357)	$ (18,394)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment	19	(4)	21	(9)
Change in unrealized gain (loss) on available-for-sale debt securities	4	37	(25)	121
Comprehensive loss	$ (14,930)	$ (9,222)	$ (27,361)	$ (18,282)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2019	$ 106,690	$ 3	$ 247,282	$ (6)	$ (140,589)
Beginning balance, shares at Dec. 31, 2019		31,243,029
Proceeds from exercise of stock options	1,013		1,013
Proceeds from exercise of stock options, shares		513,993
Proceeds from Employee Stock Purchase Plan purchases	631		631
Proceeds from Employee Stock Purchase Plan purchases, shares		71,480
Restricted stock units vested, shares		43,620
Stock-based compensation	3,071		3,071
Foreign currency translation adjustment	(9)			(9)
Unrealized gain (loss) on available-for-sale debt securities	121			121
Net loss	(18,394)				(18,394)
Ending balance at Jun. 30, 2020	93,123	$ 3	251,997	106	(158,983)
Ending balance, shares at Jun. 30, 2020		31,872,122
Beginning balance at Mar. 31, 2020	99,202	$ 3	248,854	73	(149,728)
Beginning balance, shares at Mar. 31, 2020		31,530,443
Proceeds from exercise of stock options	690		690
Proceeds from exercise of stock options, shares		236,578
Proceeds from Employee Stock Purchase Plan purchases	631		631
Proceeds from Employee Stock Purchase Plan purchases, shares		71,480
Restricted stock units vested, shares		33,621
Stock-based compensation	1,822		1,822
Foreign currency translation adjustment	(4)			(4)
Unrealized gain (loss) on available-for-sale debt securities	37			37
Net loss	(9,255)				(9,255)
Ending balance at Jun. 30, 2020	93,123	$ 3	251,997	106	(158,983)
Ending balance, shares at Jun. 30, 2020		31,872,122
Beginning balance at Dec. 31, 2020	194,945	$ 4	376,788	22	(181,869)
Beginning balance, shares at Dec. 31, 2020		39,105,548
Proceeds from follow-on equity offering, net of offering costs	161,916		161,916
Proceeds from follow-on equity offering, net of offering costs, shares		4,542,500
Proceeds from exercise of stock options	1,399		1,399
Proceeds from exercise of stock options, shares		384,938
Proceeds from Employee Stock Purchase Plan purchases	1,191		1,191
Proceeds from Employee Stock Purchase Plan purchases, shares		57,001
Restricted stock units vested, shares		119,981
Stock-based compensation	6,657		6,657
Foreign currency translation adjustment	21			21
Unrealized gain (loss) on available-for-sale debt securities	(25)			(25)
Net loss	(27,357)				(27,357)
Ending balance at Jun. 30, 2021	338,747	$ 4	547,951	18	(209,226)
Ending balance, shares at Jun. 30, 2021		44,209,968
Beginning balance at Mar. 31, 2021	348,420	$ 4	542,694	(5)	(194,273)
Beginning balance, shares at Mar. 31, 2021		43,798,661
Proceeds from exercise of stock options	466		466
Proceeds from exercise of stock options, shares		270,912
Proceeds from Employee Stock Purchase Plan purchases	1,191		1,191
Proceeds from Employee Stock Purchase Plan purchases, shares		57,001
Restricted stock units vested, shares		83,394
Stock-based compensation	3,600		3,600
Foreign currency translation adjustment	19			19
Unrealized gain (loss) on available-for-sale debt securities	4			4
Net loss	(14,953)				(14,953)
Ending balance at Jun. 30, 2021	$ 338,747	$ 4	$ 547,951	$ 18	$ (209,226)
Ending balance, shares at Jun. 30, 2021		44,209,968

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net loss	$ (27,357)	$ (18,394)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation expense	6,657	3,071
Depreciation and amortization	2,909	2,815
Noncash operating lease cost	856	689
Amortization of premium (discount) on short-term investments	1,012	(34)
Other	71	(9)
Changes in operating assets and liabilities
Accounts receivable	(2,928)	(2,075)
Inventory and other deferred costs	(1,682)	(1,918)
Prepaid expenses and other assets	(4,991)	396
Accounts payable	(75)	(348)
Accrued and other current liabilities	(1,390)	(797)
Contract liabilities	(9,573)	(7,025)
Operating lease liabilities	(819)	(496)
Other long-term liabilities	(364)	128
Net cash used in operating activities	(37,674)	(23,997)
Cash flows from investing activities:
Purchases of available-for-sale debt securities	(206,672)	(67,108)
Proceeds from maturities of available-for-sale debt securities	76,508	60,313
Proceeds from sales of available-for-sale debt securities	5,059
Purchases of property and equipment	(4,544)	(855)
Net cash used in investing activities	(129,649)	(7,650)
Cash flows from financing activities:
Proceeds from public offerings, net of underwriting discounts and commissions	162,258
Payments of costs related to public offerings	(342)
Proceeds from loans	5,167
Repayments of loans	(815)
Proceeds from exercise of equity awards	2,591	1,644
Net cash provided by financing activities	168,859	1,644
Effect of exchange rates on cash flows and cash equivalents	19	(1)
Net change in cash and cash equivalents	1,555	(30,004)
Cash and cash equivalents, beginning of period	68,525	55,046
Cash and cash equivalents, end of period	$ 70,080	$ 25,042

Company and Nature of Business

Company and Nature of Business	6 Months Ended
	Jun. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Company and Nature of Business	Note 1. Company and Nature of Business Personalis, Inc. (the “Company”) was incorporated in Delaware on February 21, 2011 and began operations in September 2011. The Company formed a wholly owned subsidiary, Personalis (UK) Ltd., in August 2013 and a wholly owned subsidiary, Shanghai Personalis Biotechnology Co., Ltd., which is referred to as “Personalis (Shanghai) Ltd” herein, in October 2020. The Company is a growing cancer genomics company transforming the development of next-generation therapies by providing more comprehensive molecular data about each patient’s cancer and immune response. The Company provides sequencing and data analysis services to support the development of cancer therapies. The Company also provides sequencing and data analysis services to support population sequencing initiatives, which accounts for the majority of revenue. Cancer genomic services are sold primarily to pharmaceutical companies, biopharmaceutical companies, universities, non-profits, and government entities, while services for population sequencing initiatives are sold primarily to government entities. The principal markets for the Company’s services are the United States and Europe. In June 2020, the Company began partnering with a clinical genomics and life sciences company headquartered in China to expand business operations into China. The Company has incurred losses to date and expects to incur additional losses for the foreseeable future. The Company continues to invest the majority of its resources in the development and growth of its business, including investments in product development and sales and marketing efforts. The Company’s activities have been financed to date primarily through the sale of equity securities and cash from operations .

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Basis of Presentation The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and the applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim reporting. Certain information and note disclosures normally included in the 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 consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The condensed consolidated financial statements include the accounts of Personalis, Inc. and its wholly owned subsidiaries, Personalis (UK) Ltd. and Personalis (Shanghai) Ltd. All intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements reflect all normal recurring adjustments that are necessary to present fairly the results for the interim periods presented. Interim results are not necessarily indicative of the results for the full year ending December 31, 2021. Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The estimates include, but are not limited to, useful lives assigned to long-lived assets, the valuation of stock options, the valuation of stock-based awards, and provisions for income taxes and contingencies. Actual results could differ from these estimates, and such differences could be material to the Company’s condensed consolidated financial position and results of operations. Follow-On Equity Offerings On August 14, 2020, the Company completed a follow-on equity offering in which it issued and sold 6,578,947 shares of its common stock at a public offering price of $19.00 per share. The Company received net proceeds of $117.5 million after deducting underwriting discounts and commissions. The Company also incurred $0.4 million of offering costs, including legal, accounting, printing and other offering-related costs. On January 29, 2021, the Company completed a follow-on equity offering in which it issued and sold 3,950,000 shares of its common stock at a public offering price of $38.00 per share. The Company received net proceeds of $141.1 million after deducting underwriting discounts and commissions. The underwriters of the offering exercised their option to purchase an additional 592,500 shares shortly thereafter, resulting in additional net proceeds of $21.2 million after deducting underwriting discounts and commissions. The Company also incurred $0.3 million of offering costs, including legal, accounting, printing and other offering-related costs. Concentration of Credit Risk and Other Risks and Uncertainties The Company is subject to credit risk from its portfolio of cash and cash equivalents. The Company’s cash and cash equivalents are deposited with high-quality financial institutions. Deposits at these institutions may, at times, exceed federally insured limits. Management believes these financial institutions are financially sound and, accordingly, that minimal credit risk exists. The Company also invests in investment ‑ ‑ The Company purchases various reagents and sequencing materials from sole source suppliers. Any extended interruption in the supply of these materials could result in the Company’s inability to secure sufficient materials to conduct business and meet customer demand. The Company routinely assesses the creditworthiness of its customers and does not require collateral. The Company has not experienced any material losses related to receivables from individual customers, or groups of customers. The Company maintains an allowance for doubtful accounts, which was $0.1 Significant customers are those that represent more than 10% of the Company’s total revenue in each period or accounts receivable balance at each respective balance sheet date. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows: Revenue Accounts Receivable Three Months Ended June 30, Six Months Ended June 30, June 30, 2021 December 31, 2020 2021 2020 2021 2020 VA MVP 62% 76% 63% 76% 11% * Pfizer Inc. 15% 10% 14% * 50% * Merck & Co., Inc. * * * * 12% 59% * Less than 10% of revenue or accounts receivable Revenue Recognition The Company applies the revenue recognition guidance in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“Topic 606”). Revenue Recognition The revenue guidance provides a five-step framework through which revenue is recognized when control of promised goods or services is transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To determine revenue recognition for arrangements that the Company concludes are within the scope of Topic 606, management performs the following five steps: (i) identifies the contract(s) with a customer; (ii) identifies the performance obligations in the contract(s); (iii) determines the transaction price, including whether there are any constraints on variable consideration; (iv) allocates the transaction price to the performance obligations; and (v) recognizes revenue when (or as) the Company satisfies a performance obligation. At contract inception, once a contract is determined to be within the scope of the new revenue standard, the Company assesses whether individual goods or services promised within each contract are distinct and, therefore, represent separate performance obligations. The Company derives revenue from sequencing and data analysis services to support the development of personalized cancer vaccines and other next-generation cancer immunotherapies, as well as to support population sequencing initiatives. The Company’s contracts are in the form of a combination of signed agreements, statements of work, and/or purchase orders. Under Topic 606, the Company accounts for a contract with a customer when there is approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance, and it is probable that the Company will collect substantially all of the consideration to which it will be entitled. The sequencing and data analysis services are the only distinct services that meet the definition of a performance obligation and are accounted for as one performance obligation under Topic 606. The Company recognizes revenue from such services at the point in time when control of the test results is transferred to the customer. The Company has elected to exclude all sales and value added taxes from the measurement of the transaction price. Sequencing and data analysis services are based on a fixed price per test. Payment terms and conditions vary by contract and customer. The Company’s standard payment terms are less than 90 days from the invoice date. In instances where the timing of the Company’s revenue recognition differs from the timing of its invoicing, the Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised services to the customer will be one year or less. After assessing each of its revenue-generating arrangements to determine whether a significant financing component exists, the Company concluded that a significant financing component does not exist in any of its arrangements. The primary purpose of the Company’s invoicing terms is to provide customers with simplified and predictable ways of purchasing the Company’s services and to provide payment protection for the Company. Practical Expedients and Exemptions As a practical expedient, the Company recognizes the incremental costs of obtaining contracts, such as sales commissions, as an expense when incurred since the amortization period of the asset the Company otherwise would have recognized is one year or less. Sales commissions are recorded within selling, general and administrative expenses in the condensed consolidated statements of operations. Cost of Revenue Cost of revenue consists of raw materials costs, personnel costs (salaries, bonuses, benefits, payroll taxes, and stock-based compensation), laboratory supplies and consumables, depreciation and maintenance on equipment, and allocated facilities and information technology (“IT”) costs. Research and Development Expenses The Company charges research and development costs to expenses as incurred, including lab and automation development costs. The expenses primarily consist of personnel costs (salaries, bonuses, stock-based compensation, payroll taxes, and benefits), laboratory supplies and consumables, costs of purchasing samples for research purposes, depreciation and maintenance on equipment, and allocated facilities and IT costs. Stock-Based Compensation For options granted to employees, non-employees, and directors, stock-based compensation is measured at grant date based on the fair value of the award. The Company determines the grant-date fair value of options using the Black-Scholes option-pricing model, except for certain performance-based awards for which an alternative valuation method may be used. The Company determines the fair value of restricted stock unit awards using the closing market price of the Company’s common stock on the date of grant. The grant-date fair value of awards is amortized over the employees’ requisite service period on a straight-line basis, or the non-employees’ vesting period as the goods are received or services rendered. Forfeitures are accounted for as they occur. Additionally, the Company’s 2019 Employee Stock Purchase Plan (the “ESPP”) is deemed to be a compensatory plan and therefore is included in stock-based compensation expense. Inputs used in Black-Scholes option-pricing models to measure fair value of options are summarized as follows: Expected Term. The expected term is calculated using the simplified method, which is available if there is insufficient historical data about exercise patterns and post-vesting employment termination behavior. The simplified method is based on the vesting period and the contractual term for each grant, or for each vesting tranche for awards with graded vesting. The midpoint of the vesting date and the contractual expiration date is used as the expected term under this method. For awards with multiple vesting tranches, the assumed period for each tranche is computed separately and then averaged together to determine the expected term for the award. Expected Volatility. The Company used an average historical stock price volatility of a peer group of publicly traded companies to be representative of its expected future stock price volatility, as the Company did not have sufficient trading history for its common stock. For purposes of identifying these peer companies, the Company considered the industry, stage of development, size, and financial leverage of potential comparable companies. For each grant, the Company measured historical volatility over a period equivalent to the expected term. Risk-Free Interest Rate. The risk-free interest rate is based on the implied yield currently available on U.S. Treasury zero-coupon issues with remaining terms equivalent to the expected term of a stock award. Expected Dividend Rate. The Company has not paid and does not anticipate paying any dividends in the near future. Accordingly, the Company has estimated the dividend yield to be Cash and Cash Equivalents Cash equivalents consist of highly liquid investments with maturities at the time of purchase of three months or less. Cash equivalents include bank demand deposits and money market accounts that invest primarily in cash, U.S. Treasury bills, notes, and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities, and repurchase agreements secured by such obligations or cash. Cash equivalents also include commercial paper and U.S. agency bonds, which are marketable debt securities recorded at fair value and accounted for in the same manner as other marketable debt securities described below. Short-term Investments The Company’s investments in marketable debt securities are classified as available-for-sale and recorded at fair value. Investments with original maturities of greater than three months and remaining maturities of less than one year are classified as short-term investments. Investments with maturities beyond one year may be classified as short-term based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. Short-term investments primarily consist of U.S. agency bonds, commercial paper, corporate bonds, asset-backed securities, and U.S. treasuries. Unrealized gains and losses are included in accumulated other comprehensive income (loss) in stockholders’ equity. Any discount or premium arising at purchase is accreted or amortized to interest income or expense. Realized gains and losses and declines in fair value, if any, judged to be other than temporary are reported in other income (expense), net. When securities are sold, any associated unrealized gain or loss initially recorded as a separate component of stockholders’ equity is reclassified out of stockholders’ equity on a specific-identification basis and recorded in earnings for the period. The Company periodically evaluates whether declines in fair values of its investments below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company’s ability and intent to hold the marketable security until a forecasted recovery occurs. Factors considered include quoted market prices, recent financial results and operating trends, implied values from any recent transactions or offers of investee securities, credit quality of debt instrument issuers, other publicly available information that may affect the value of the marketable security, duration and severity of the decline in value, and management’s strategy and intentions for holding the marketable security. To date, the Company has not recorded any impairment charges on its marketable securities related to other-than-temporary declines in market value. Fair Value Measurements Financial assets and liabilities are recorded at fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The hierarchy below lists three levels of fair value based on the extent to which inputs used in measuring fair value are observable in the market. Observable inputs reflect market data obtained from independent sources while unobservable inputs reflect market assumptions made by the reporting entity. The three-level hierarchy for the inputs to valuation techniques used to measure fair value is briefly summarized as follows: Level 1 — Unadjusted quoted prices in active markets that are accessible to the reporting entity at the measurement date for identical assets and liabilities. Level 2 — Inputs other than quoted prices in active markets for identical assets and liabilities that are observable either directly or indirectly for substantially the full term of the asset or liability. Level 2 inputs include the following: • Quoted prices for similar assets and liabilities in active markets. • Quoted prices for identical or similar assets or liabilities in markets that are not active. • Observable inputs other than quoted prices that are used in the valuation of the asset or liabilities (e.g., interest rate and yield curve quotes at commonly quoted intervals). • Inputs that are derived principally from or are corroborated by observable market data by correlation or other means. Level 3 — Unobservable inputs for the assets or liabilities (i.e., supported by little or no market activity). Level 3 inputs include management’s own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk). This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. Inventory and Other Deferred Costs Inventory, consisting of supplies used in the Company’s genomic analysis contracts, are valued at the lower of cost or net realizable value. Cost is determined using actual costs, on a first-in, first-out basis. Other deferred costs relate to work in process for costs incurred on genomic analysis contracts that have not been completed or recognized as revenue. Other deferred costs represent materials used in sequencing services, labor, and overhead allocations. Leases The Company categorizes leases with contractual terms longer than twelve months as either operating or finance leases. Finance leases are generally those leases that allow the Company to substantially utilize or pay for the entire asset over its estimated life. All other leases are categorized as operating leases. As of June 30, 2021, the Company had no finance leases. Certain lease contracts include obligations to pay for other services, such as maintenance. The Company elected to account for these other services as a component of the lease (i.e., the Company elected the practical expedient not to separate lease and non-lease components). Lease liabilities are recognized at the present value of the fixed lease payments, reduced by landlord incentives, using a discount rate based on the Company’s current borrowing rate at the lease commencement date, adjusted for various factors including level of collateralization and term (the “incremental borrowing rate”), unless the rate implicit in the lease is readily determinable. The current portion of lease liabilities is included in “Accrued and other current liabilities.” Lease assets are recognized based on the initial present value of the fixed lease payments, reduced by landlord incentives, plus any direct costs from executing the leases or lease prepayments reclassified from “Other long-term assets” upon lease commencement. Lease assets are presented as “Operating lease right-of-use assets” as a long-term asset. Leasehold improvements are capitalized at cost and amortized over the lesser of their expected useful life or the lease term. Costs associated with operating lease assets are recognized on a straight-line basis within operating expenses over the term of the lease. The Company has made an accounting policy election not to recognize right-of-use assets and lease liabilities that arise from leases with a term of 12 months or less. Lease payments are recognized as an expense on a straight-line basis over the lease term. Recent Accounting Pronouncements New Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables. The accounting update also made minor changes to the impairment model for available-for-sale debt securities. In November 2019, the FASB delayed the effective date for Topic 326 as applicable to smaller reporting companies to the first quarter of 2023. While the Company will no longer qualify as a smaller reporting company starting in the first quarter of 2022, the delayed effective date still applies to the Company. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements and related disclosures. The Company will apply the new guidance by means of a cumulative-effect adjustment to the opening retained earnings as of the beginning of the first reporting period in which the guidance is effective. JOBS Act Accounting Election The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has irrevocably elected not to avail itself of this exemption from new or revised accounting standards, and therefore, the Company will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

Revenue

Revenue	6 Months Ended
	Jun. 30, 2021
Revenue From Contract With Customer [Abstract]
Revenue	Note 3. Revenue The following table presents revenue disaggregated by customer type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 VA MVP $ 13,507 $ 14,750 $ 26,717 $ 29,506 All other customers 8,163 4,745 15,834 9,150 Total revenue $ 21,670 $ 19,495 $ 42,551 $ 38,656 Revenue from countries outside of the United States, based on the billing addresses of customers, represented approximately 6% and 1% of the Company’s revenue for the three months ended June 30, 2021 and 2020, and approximately 7% and 5% for the six months ended June 30, 2021 and 2020, respectively. Contract Assets and Liabilities Contract assets as of June 30, 2021 and December 31, 2020 were immaterial. The Company’s contract liabilities consist of customer deposits in excess of revenue recognized and are presented as current liabilities in the condensed consolidated balance sheets. The balance of contract liabilities was $11.5 million and $21.0 million as of June 30, 2021 and December 31, 2020, respectively. Revenue recognized for the three months ended June 30, 2021 and 2020 that were included in the contract liability balance at the beginning of each reporting period were $9.8 million and $10.8 million, respectively. Revenue allocated to remaining performance obligations represent contracted revenue that has not yet been recognized (“contracted not recognized revenue”), which include VA MVP contract liabilities and amounts that will be invoiced and recognized as revenue in future periods. Contracted not recognized revenue was $16.8 million as of June 30, 2021, the substantial majority of which is expected to be recognized as revenue within the next quarter. The Company has elected the optional exemption that allows for the exclusion of contracts with an original expected duration of one year or less.

Balance Sheet Details

Balance Sheet Details	6 Months Ended
	Jun. 30, 2021
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Details	Note 4. Balance Sheet Details Inventory and other deferred costs consist of the following (in thousands): June 30, December 31, 2021 2020 Raw materials $ 4,225 $ 2,675 Other deferred costs 3,096 2,964 Total inventory and other deferred costs $ 7,321 $ 5,639 Property and equipment. Depreciation and amortization expense for the three months ended June 30, 2021 and 2020 was $1.4 million, and for the six months ended June 30, 2021 and 2020 was $2.9 million and $2.8 million, respectively. Accumulated depreciation and amortization was $15.9 million and $14.5 million as of June 30, 2021 and December 31, 2020, respectively. Accrued and other current liabilities consist of the following (in thousands): June 30, December 31, 2021 2020 Accrued compensation $ 6,219 $ 8,041 Operating lease liabilities 3,360 2,445 Loans—current portion (Note 6) 2,786 — Employee ESPP contributions 462 407 Accrued liabilities 435 313 Accrued taxes 446 95 Total accrued and other current liabilities $ 13,708 $ 11,301

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 5. Fair Value Measurements The following tables show the Company’s financial assets measured at fair value on a recurring basis and the level of inputs used in such measurements as of June 30, 2021 and December 31, 2020 (in thousands): June 30, 2021 Adjusted Cost Unrealized Gains Unrealized Losses Fair Value Fair Value Level Assets Cash and cash equivalents: Cash $ 6,565 $ — $ — $ 6,565 Money market funds 21,523 — — 21,523 Level 1 Commercial paper 41,993 — (1 ) 41,992 Level 2 Total cash and cash equivalents 70,081 — (1 ) 70,080 Short-term investments: Asset-backed securities 18,277 2 (2 ) 18,277 Level 2 Commercial paper 135,889 3 (4 ) 135,888 Level 2 Corporate debt securities 24,377 1 (3 ) 24,375 Level 2 U.S. agency securities 24,056 9 — 24,065 Level 2 U.S. government securities 56,230 4 (12 ) 56,222 Level 2 Total short-term investments 258,829 19 (21 ) 258,827 Total assets measured at fair value $ 328,910 $ 19 $ (22 ) $ 328,907 December 31, 2020 Adjusted Cost Unrealized Gains Unrealized Losses Fair Value Fair Value Level Assets Cash and cash equivalents: Cash $ 4,767 $ — $ — $ 4,767 Money market funds 22,614 — — 22,614 Level 1 Commercial paper 41,145 — (1 ) 41,144 Level 2 Total cash and cash equivalents 68,526 — (1 ) 68,525 Short-term investments: Commercial paper 25,470 — — 25,470 Level 2 Corporate debt securities 29,576 — (8 ) 29,568 Level 2 U.S. agency securities 61,436 31 (1 ) 61,466 Level 2 U.S. government securities 18,260 1 — 18,261 Level 2 Total short-term investments 134,742 32 (9 ) 134,765 Total assets measured at fair value $ 203,268 $ 32 $ (10 ) $ 203,290 Realized gains or losses on marketable securities are immaterial for the periods presented. No security has been in an unrealized loss position for 12 months or greater. The Company determined that it did have the ability and intent to hold all marketable securities that have been in a continuous loss position until maturity or recovery. As of June 30, 2021, the Company does not consider any of its marketable debt securities to be other-than-temporarily impaired. The Company’s marketable debt securities at June 30, 2021 have maturities due in one year or less, except for debt securities with an aggregate cost basis and fair value of $34.7 million that have maturities ranging from 13 to 21 months.

Loans

Loans	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Loans	Note 6. Loans In April 2021, the Company entered into a payment agreement with a financing entity to finance the purchase of $2.4 million of certain internal use software licenses and related software maintenance from a vendor. The financing entity and vendor are not related. The Company is obligated to repay the financed amount in three equal payments of $0.8 million in May 2021, May 2022, and May 2023. The payment agreement is noninterest bearing and the Company concluded that such interest rate (zero) did not represent fair and adequate compensation to the financing entity for the use of the related funds. Accordingly, the Company approximated the rate at which it could obtain financing of a similar nature from other sources at the date of the transaction. The resulting imputed interest rate was 7% and was used to establish the present value of the payment agreement. The discount is recognized as interest expense in the condensed consolidated statements of operations over the life of the payment agreement. In April 2021, the Company entered into another payment agreement, with the same financing entity, to finance the purchase of $3.1 million of certain computer hardware and related hardware maintenance. The Company is required to pay three equal payments of $1.04 million in July 2021, June 2022, and June 2023. The nature of this agreement and resulting accounting treatment are the same as the payment agreement described in the preceding paragraph. The total initial present value of the payment agreements was $ 5.2 million and presented as proceeds from loans in the condensed consolidated statements of cash flows. Such proceeds were used to purchase equipment, software, and related maintenance and are reflected as cash outflows in the investing and operating activities sections in the condensed consolidated statements of cash flows. Repayments are presented as financing cash outflows in the condensed consolidated statements of cash flows. Interest expense for the three and six months ended June 30, 2021 was $ 0.1 million. Amounts outstanding under the payment agreements are as follows (in thousands): June 30, December 31, 2021 2020 Principal $ 4,757 $ — Less: unamortized discount (339 ) — Total carrying amount 4,418 — Less: current portion (included in “Accrued and other current liabilities”) (2,786 ) — Long-term portion (included in “Other long-term liabilities”) $ 1,632 $ —

Leases

Leases	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Leases	Note 7. Leases In February 2015, the Company entered into a noncancelable operating lease for approximately 31,280 square feet of space used for its current laboratory and corporate headquarters. In April 2020, the Company extended the term of the lease through November 30, 2027. The lease includes an option to extend the term for a period of three years with rent payments equal to then current fair market rent for the space. The Company determined the extension option is not reasonably certain to be exercised. The lease contains a leasehold improvement incentive and escalating rent payments. In May 2021, the Company amended the lease to expand the premises subject to the lease to include an additional 14,710 square feet of space (the “Expansion Lease”). The Expansion Lease expires on December 31, 2022 and has no option to extend the term. In August 2019, the Company entered into a noncancelable operating lease for a co-located data center space. The lease expires on August 31, 2022 and includes an option to extend the term for a period of three years immediately following the expiration of the term with rent payments to be negotiated upon such a renewal. The Company determined the extension option is not reasonably certain to be exercised. In April 2020, the lease was modified to increase the data center space available for the Company’s use for the remainder of the lease term. Operating lease cost for the three months ended June 30, 2021 and 2020 was $0.7 million, and for the six months ended June 30, 2021 and 2020 was $1.4 million and $1.0 million, respectively. As of June 30, 2021, the Company’s operating leases had a weighted-average remaining lease term of 5.4 years and a weighted-average discount rate of 10.3%. The Company’s discount rates are based on estimates of its incremental borrowing rate, as the discount rates implicit in the leases cannot be readily determined. Future lease payments under operating leases as of June 30, 2021 were as follows (in thousands): Amount 2021 (remaining six months) $ 1,841 2022 3,318 2023 2,046 2024 2,113 2025 2,181 2026 and thereafter 4,378 Total future minimum lease payments 15,877 Less: imputed interest (3,999 ) Present value of future minimum lease payments 11,878 Less: current portion of operating lease liability (3,360 ) Long-term operating lease liabilities $ 8,518 Cash paid for operating lease liabilities, included in cash flow s from operating activities in the condensed consolidated statement of cash flows, for the six months ended June 30 , 2021 and 2020 , was $ million and $ million, respectively . Right-of-use assets obtained in exchange for new operating lease liabilities during the six months ended June 30, 2021 and 2020 were $ 1.7 million and $ 9.8 million, respectively.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	Note 8. Stock-Based Compensation 2011 Equity Incentive Plan In 2011, the Company’s board of directors established its 2011 Equity Incentive Plan (the “2011 Plan”) that provided for the granting of stock options to employees and nonemployees of the Company. Under the 2011 Plan, the Company had the ability to issue incentive stock options (“ISOs”), nonstatutory stock options (“NSOs”), stock appreciation rights, restricted stock awards, and restricted stock unit awards (“RSUs”). Options under the 2011 Plan could be granted for periods of up to 10 years. The ISOs could be granted at a price per share not less than the fair value at the date of grant. 2019 Equity Incentive Plan The Company’s board of directors adopted and the Company’s stockholders approved the 2019 Equity Incentive Plan (the “2019 Plan”) in May 2019 and June 2019, respectively. The 2019 Plan became effective in June 2019 in connection with the Company’s Initial Public Offering (“IPO”), and no further grants will be made under the 2011 Plan. Shares reserved and remaining available for issuance under the 2011 Plan were added to the 2019 Plan reserve upon its effectiveness. The 2019 Plan provides for the grant of ISOs, NSOs, stock appreciation rights, restricted stock awards, RSUs, performance-based stock awards, and other forms of equity compensation. Additionally, the 2019 Plan provides for the grant of performance cash awards. ISOs may be granted only to the Company’s employees and to any of the Company’s parent or subsidiary corporation’s employees. All other awards may be granted to employees, including officers, and to non-employee directors and consultants of the Company and any of the Company’s affiliates. The exercise price of a stock option generally cannot be less than 100% of the fair market value of the Company’s common stock on the date of grant. Options under the 2019 Plan may be granted for periods of up to 10 years. 2020 Inducement Plan The Compensation Committee of the Company’s board of directors adopted the 2020 Inducement Plan (the “Inducement Plan”) in May 2020, which became effective upon adoption. The Inducement Plan was adopted without stockholder approval, as permitted by the Nasdaq Stock Market listing rules (the “Nasdaq Listing Rules”). The Inducement Plan provides for the grant of equity-based awards, including NSOs, stock appreciation rights, restricted stock awards, RSUs, performance-based stock awards, and other forms of equity compensation, and its terms are substantially similar to the stockholder-approved 2019 Plan. In accordance with relevant Nasdaq Listing Rules, awards under the Inducement Plan may only be made to individuals not previously employees or non-employee directors of the Company (or following such individuals’ bona fide period of non-employment with the Company), as an inducement material to the individuals entry into employment with the Company. 2019 Employee Stock Purchase Plan The Company’s board of directors adopted and the Company’s stockholders approved the ESPP in May 2019 and June 2019, respectively. Subject to any plan limitations, the ESPP allows eligible employees to contribute, normally through payroll deductions, up to 15 of their earnings for the purchase of the Company’s common stock at a discounted price per share. The price at which common stock is purchased under the ESPP is equal to 85% of the fair market value of the Company’s common stock on the first or last day of the offering period, whichever is lower. The ESPP provides for separate six-month offering periods beginning on May 1 and November 1 of each year. Shares of common stock available for issuance under the Company’s equity incentive plans as of June 30, 2021 and December 31, 2020 were as follows: June 30, December 31, 2021 2020 Reserved for issuance upon exercise of options outstanding under the 2011 Plan 3,030,494 3,389,711 Reserved for issuance upon exercise or settlement of awards outstanding under the 2019 Plan 3,416,066 2,399,513 Reserved and available for issuance under the 2019 Plan 2,783,091 1,977,069 Reserved for issuance upon exercise or settlement of awards outstanding under the Inducement Plan 185,100 199,300 Reserved and available for issuance under the Inducement Plan 801,900 800,700 Reserved and available for issuance under the ESPP 654,636 320,582 Total number of shares reserved 10,871,287 9,086,875 Stock Option Activity A summary of the Company’s stock option activity (excluding performance-based stock option activity summarized further below) under the 2011 Plan, 2019 Plan, and Inducement Plan for the six months ended June 30, 2021 is as follows: Outstanding Options (in thousands, except share and per share data) Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance—December 31, 2020 4,948,306 $ 7.10 6.71 $ 146,044 Options granted 728,306 21.89 Options exercised (384,938 ) 3.64 Options cancelled (66,460 ) 9.99 Balance—June 30, 2021 5,225,214 $ 9.38 6.76 $ 84,982 Options vested and exercisable as of June 30, 2021 3,118,662 $ 5.17 5.29 $ 62,790 Options granted to new hires generally vest over a four-year four-year The aggregate intrinsic value of unexercised stock options is calculated as the difference between the closing price of the Company’s common stock of $25.30 on June 30, 2021 and the exercise prices of the underlying stock options. Out-of-the money stock options are excluded from the aggregate intrinsic value. The weighted-average grant date fair value of options granted was $12.34 and $6.70 per share for the three months ended June 30, 2021 and 2020, and $13.55 and $4.81 per share for the six months ended June 30, 2021 and 2020, respectively. As of June 30, 2021, the unrecognized stock-based compensation cost of unvested options was $19.0 million, which is expected to be recognized over a weighted-average period of 2.5 years. Valuation of Stock Options The Company estimated the fair value of stock options (excluding performance-based stock options discussed below) using the Black-Scholes option-pricing model. The fair value of stock options is recognized on a straight-line basis over the requisite service periods of the awards. The fair value of stock options was estimated using the following weighted-average assumptions: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Expected term (in years) 5.50 - 6.27 5.50 - 6.08 5.50 - 6.27 5.50 - 6.08 Volatility 69.39 - 69.90% 67.58 - 68.18% 68.06 - 69.90% 61.74 - 68.18% Risk-free interest rate 0.94 - 1.06% 0.36 - 0.44% 0.62 - 1.06% 0.36 - 1.66% Dividend yield –% –% –% –% Performance-Based Stock Option Activity Pursuant to the 2019 Plan, in March 2020, the Company’s board of directors granted the Company’s Chief Executive Officer a performance-based stock option (“PSO”) to purchase 421,000 shares of common stock. The PSO was subject to the Chief Executive Officer’s continued service to the Company through the date of vesting and, if the performance condition is not met within 10 years from the date of grant, the PSO would be canceled. The shares subject to the PSO would vest in full if the Company’s average market capitalization is equal to or greater than $1 billion over a 30 calendar day period. Upon a change in control, the vesting of the shares subject to the PSO would accelerate on a pro rata basis based on the price per share in such change in control transaction multiplied by the price per share at such time divided by $1 billion, with up to 100% of the shares eligible for such accelerated vesting. During the last quarter of 2020, the Company’s average market capitalization was equal to or greater than $1 billion over a 30 calendar day period and the PSO vested in full. A summary of the Company’s performance-based stock option activity under the 2019 Plan for the six months ended June 30, 2021 is as follows: Outstanding Performance-Based Options (in thousands, except share and per share data) Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance—December 31, 2020 421,000 $ 5.10 9.21 $ 13,266 Options granted — Options exercised — Options cancelled — Balance—June 30, 2021 421,000 $ 5.10 8.71 $ 8,504 Options vested and exercisable as of June 30, 2021 421,000 $ 5.10 8.71 $ 8,504 The aggregate intrinsic value of unexercised stock options is calculated as the difference between the closing price of the Company’s common stock of $25.30 on June 30, 2021 and the exercise price of the underlying stock options. As of June 30, 2021, there is no remaining unrecognized stock-based compensation cost. Valuation of Performance-Based Stock Options The Company estimated the fair value of the PSO using a Monte Carlo Model and the following assumptions and estimates: 2020 Performance period (in years) 10.00 Derived service period (in years) 4.55 Volatility 63.60 % Risk-free interest rate 1.02 % Dividend yield –% Estimated fair value per share $ 3.31 Restricted Stock Units Activity and Valuation A summary of the Company’s RSU activity under the 2019 Plan and Inducement Plan for the six months ended June 30, 2021 is as follows: Unvested Restricted Stock Units (in thousands, except share and per share data) Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Balance—December 31, 2020 619,218 $ 10.41 $ 22,670 RSUs granted 514,496 22.94 RSUs vested (119,981 ) 8.51 2,955 RSUs cancelled (28,287 ) 15.86 Balance—June 30, 2021 985,446 $ 17.03 $ 24,932 The Company granted RSUs to employees to receive shares of the Company’s common stock. The RSUs awarded are subject to each individual’s continued service to the Company through each applicable vesting date. RSUs granted to new hires generally vest annually over a four-year four-year three-year The aggregate fair value of unvested RSUs is calculated using the closing price of the Company’s common stock of $25.30 on June 30, 2021. As of June 30, 2021, the unrecognized stock-based compensation cost of unvested RSUs was $15.6 million, which is expected to be recognized over a weighted-average period of 2.9 years. The Company's default tax withholding method for RSUs is the sell-to-cover method, in which shares with a market value equivalent to the tax withholding obligation are sold on behalf of the holder of the RSUs upon vesting and settlement to cover the tax withholding liability and the cash proceeds from such sales are remitted by the Company to taxing authorities. ESPP Activity and Valuation During the six months ended June 30, 2021 and 2020, 57,001 Three and Six Months Ended June 30, 2021 2020 Expected term (in years) 0.49 0.50 Volatility 74.88 % 102.10 % Risk-free interest rate 0.04 % 0.12 % Dividend yield –% –% Grant-date fair value per share $ 8.21 $ 4.29 Stock Option Modifications During March 2021, the Company’s board of directors approved modifications to the outstanding stock options of two of the Company’s non-employee directors. The modifications involved acceleration of unvested options and an extension of the exercise periods. The modifications resulted in incremental compensation cost of $1.2 million, all of which was recognized during the six months ended June 30, 2021. During the three months ended June 30, 2021, $0.6 million of such incremental compensation was recognized. Stock-Based Compensation Expense The following is a summary of stock-based compensation expense by award type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Stock options $ 2,325 $ 1,259 $ 4,503 $ 2,262 RSUs 1,011 310 1,655 423 ESPP 264 177 499 297 Performance-based stock options — 76 — 89 Total stock-based compensation expense $ 3,600 $ 1,822 $ 6,657 $ 3,071 The following is a summary of stock-based compensation expense by function (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Cost of revenue $ 332 $ 209 $ 620 $ 352 Research and development 900 394 1,628 653 Selling, general and administrative 2,368 1,219 4,409 2,066 Total stock-based compensation expense $ 3,600 $ 1,822 $ 6,657 $ 3,071

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 9 . Commitments and Contingencies Contingencies The Company is subject to claims and assessments from time to time in the ordinary course of business. Accruals for litigation and contingencies are reflected in the condensed consolidated financial statements based on management’s assessment, including the advice of legal counsel, of the expected outcome of litigation or other dispute resolution proceedings and/or the expected resolution of contingencies. Liabilities for estimated losses are accrued if the potential losses from any claims or legal proceedings are considered probable and the amounts can be reasonably estimated. Significant judgment is required in both the determination of probability of loss and the determination as to whether the amount can be reasonably estimated. Accruals are based only on information available at the time of the assessment due to the uncertain nature of such matters. As additional information becomes available, management reassesses potential liabilities related to pending claims and litigation and may revise its previous estimates, which could materially affect the Company’s consolidated results of operations in a given period. As of June 30, 2021, the Company was not involved in any material legal proceedings. Indemnification In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but that have not yet been made. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. However, the Company may record charges in the future as a result of these indemnification obligations.

Basic and Diluted Net Loss Per

Basic and Diluted Net Loss Per Common Share	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Basic and Diluted Net Loss Per Common Share	Note 10. Basic and Diluted Net Loss Per Common Share Basic net loss per common share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per common share is computed using net loss and the weighted-average number of common shares outstanding plus potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include the assumed exercise of outstanding in-the-money stock options and common stock warrants, assumed release of outstanding RSUs, and assumed issuance of common stock under the ESPP using the treasury stock method. The following table sets forth the computation of net loss per common share (in thousands, except share and per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Net loss $ (14,953 ) $ (9,255 ) $ (27,357 ) $ (18,394 ) Weighted-average common shares outstanding—basic and diluted 43,960,794 31,731,628 43,113,195 31,538,329 Net loss per common share—basic and diluted $ (0.34 ) $ (0.29 ) $ (0.63 ) $ (0.58 ) The Company incurred net losses in the periods presented, and as a result, potential common shares from stock options, common stock warrants, RSUs, and the assumed release of outstanding shares under the ESPP were not included in the diluted shares used to calculate net loss per share, as their inclusion would have been anti-dilutive. The following table sets forth the potentially dilutive shares excluded from the computation of diluted net loss per common share because their effect was anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Common stock warrants — 127,598 — 127,598 Options to purchase common stock 5,646,214 5,624,766 5,646,214 5,624,766 Unvested RSUs 985,446 629,470 985,446 629,470 ESPP 69,380 95,403 69,380 95,403 Total 6,701,040 6,477,237 6,701,040 6,477,237

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and the applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim reporting. Certain information and note disclosures normally included in the 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 consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. The condensed consolidated financial statements include the accounts of Personalis, Inc. and its wholly owned subsidiaries, Personalis (UK) Ltd. and Personalis (Shanghai) Ltd. All intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated financial statements reflect all normal recurring adjustments that are necessary to present fairly the results for the interim periods presented. Interim results are not necessarily indicative of the results for the full year ending December 31, 2021.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The estimates include, but are not limited to, useful lives assigned to long-lived assets, the valuation of stock options, the valuation of stock-based awards, and provisions for income taxes and contingencies. Actual results could differ from these estimates, and such differences could be material to the Company’s condensed consolidated financial position and results of operations.
Follow-On Equity Offerings	Follow-On Equity Offerings On August 14, 2020, the Company completed a follow-on equity offering in which it issued and sold 6,578,947 shares of its common stock at a public offering price of $19.00 per share. The Company received net proceeds of $117.5 million after deducting underwriting discounts and commissions. The Company also incurred $0.4 million of offering costs, including legal, accounting, printing and other offering-related costs. On January 29, 2021, the Company completed a follow-on equity offering in which it issued and sold 3,950,000 shares of its common stock at a public offering price of $38.00 per share. The Company received net proceeds of $141.1 million after deducting underwriting discounts and commissions. The underwriters of the offering exercised their option to purchase an additional 592,500 shares shortly thereafter, resulting in additional net proceeds of $21.2 million after deducting underwriting discounts and commissions. The Company also incurred $0.3 million of offering costs, including legal, accounting, printing and other offering-related costs.
Concentration of Credit Risk and Other Risks and Uncertainties	Concentration of Credit Risk and Other Risks and Uncertainties The Company is subject to credit risk from its portfolio of cash and cash equivalents. The Company’s cash and cash equivalents are deposited with high-quality financial institutions. Deposits at these institutions may, at times, exceed federally insured limits. Management believes these financial institutions are financially sound and, accordingly, that minimal credit risk exists. The Company also invests in investment ‑ ‑ The Company purchases various reagents and sequencing materials from sole source suppliers. Any extended interruption in the supply of these materials could result in the Company’s inability to secure sufficient materials to conduct business and meet customer demand. The Company routinely assesses the creditworthiness of its customers and does not require collateral. The Company has not experienced any material losses related to receivables from individual customers, or groups of customers. The Company maintains an allowance for doubtful accounts, which was $0.1 Significant customers are those that represent more than 10% of the Company’s total revenue in each period or accounts receivable balance at each respective balance sheet date. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows: Revenue Accounts Receivable Three Months Ended June 30, Six Months Ended June 30, June 30, 2021 December 31, 2020 2021 2020 2021 2020 VA MVP 62% 76% 63% 76% 11% * Pfizer Inc. 15% 10% 14% * 50% * Merck & Co., Inc. * * * * 12% 59% * Less than 10% of revenue or accounts receivable
Revenue Recognition	Revenue Recognition The Company applies the revenue recognition guidance in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“Topic 606”). Revenue Recognition The revenue guidance provides a five-step framework through which revenue is recognized when control of promised goods or services is transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To determine revenue recognition for arrangements that the Company concludes are within the scope of Topic 606, management performs the following five steps: (i) identifies the contract(s) with a customer; (ii) identifies the performance obligations in the contract(s); (iii) determines the transaction price, including whether there are any constraints on variable consideration; (iv) allocates the transaction price to the performance obligations; and (v) recognizes revenue when (or as) the Company satisfies a performance obligation. At contract inception, once a contract is determined to be within the scope of the new revenue standard, the Company assesses whether individual goods or services promised within each contract are distinct and, therefore, represent separate performance obligations. The Company derives revenue from sequencing and data analysis services to support the development of personalized cancer vaccines and other next-generation cancer immunotherapies, as well as to support population sequencing initiatives. The Company’s contracts are in the form of a combination of signed agreements, statements of work, and/or purchase orders. Under Topic 606, the Company accounts for a contract with a customer when there is approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance, and it is probable that the Company will collect substantially all of the consideration to which it will be entitled. The sequencing and data analysis services are the only distinct services that meet the definition of a performance obligation and are accounted for as one performance obligation under Topic 606. The Company recognizes revenue from such services at the point in time when control of the test results is transferred to the customer. The Company has elected to exclude all sales and value added taxes from the measurement of the transaction price. Sequencing and data analysis services are based on a fixed price per test. Payment terms and conditions vary by contract and customer. The Company’s standard payment terms are less than 90 days from the invoice date. In instances where the timing of the Company’s revenue recognition differs from the timing of its invoicing, the Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised services to the customer will be one year or less. After assessing each of its revenue-generating arrangements to determine whether a significant financing component exists, the Company concluded that a significant financing component does not exist in any of its arrangements. The primary purpose of the Company’s invoicing terms is to provide customers with simplified and predictable ways of purchasing the Company’s services and to provide payment protection for the Company. Practical Expedients and Exemptions As a practical expedient, the Company recognizes the incremental costs of obtaining contracts, such as sales commissions, as an expense when incurred since the amortization period of the asset the Company otherwise would have recognized is one year or less. Sales commissions are recorded within selling, general and administrative expenses in the condensed consolidated statements of operations.
Costs of Revenue	Cost of Revenue Cost of revenue consists of raw materials costs, personnel costs (salaries, bonuses, benefits, payroll taxes, and stock-based compensation), laboratory supplies and consumables, depreciation and maintenance on equipment, and allocated facilities and information technology (“IT”) costs.
Research and Development Expenses	Research and Development Expenses The Company charges research and development costs to expenses as incurred, including lab and automation development costs. The expenses primarily consist of personnel costs (salaries, bonuses, stock-based compensation, payroll taxes, and benefits), laboratory supplies and consumables, costs of purchasing samples for research purposes, depreciation and maintenance on equipment, and allocated facilities and IT costs.
Stock-Based Compensation	Stock-Based Compensation For options granted to employees, non-employees, and directors, stock-based compensation is measured at grant date based on the fair value of the award. The Company determines the grant-date fair value of options using the Black-Scholes option-pricing model, except for certain performance-based awards for which an alternative valuation method may be used. The Company determines the fair value of restricted stock unit awards using the closing market price of the Company’s common stock on the date of grant. The grant-date fair value of awards is amortized over the employees’ requisite service period on a straight-line basis, or the non-employees’ vesting period as the goods are received or services rendered. Forfeitures are accounted for as they occur. Additionally, the Company’s 2019 Employee Stock Purchase Plan (the “ESPP”) is deemed to be a compensatory plan and therefore is included in stock-based compensation expense. Inputs used in Black-Scholes option-pricing models to measure fair value of options are summarized as follows: Expected Term. The expected term is calculated using the simplified method, which is available if there is insufficient historical data about exercise patterns and post-vesting employment termination behavior. The simplified method is based on the vesting period and the contractual term for each grant, or for each vesting tranche for awards with graded vesting. The midpoint of the vesting date and the contractual expiration date is used as the expected term under this method. For awards with multiple vesting tranches, the assumed period for each tranche is computed separately and then averaged together to determine the expected term for the award. Expected Volatility. The Company used an average historical stock price volatility of a peer group of publicly traded companies to be representative of its expected future stock price volatility, as the Company did not have sufficient trading history for its common stock. For purposes of identifying these peer companies, the Company considered the industry, stage of development, size, and financial leverage of potential comparable companies. For each grant, the Company measured historical volatility over a period equivalent to the expected term. Risk-Free Interest Rate. The risk-free interest rate is based on the implied yield currently available on U.S. Treasury zero-coupon issues with remaining terms equivalent to the expected term of a stock award. Expected Dividend Rate. The Company has not paid and does not anticipate paying any dividends in the near future. Accordingly, the Company has estimated the dividend yield to be
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents consist of highly liquid investments with maturities at the time of purchase of three months or less. Cash equivalents include bank demand deposits and money market accounts that invest primarily in cash, U.S. Treasury bills, notes, and other obligations issued or guaranteed as to principal and interest by the U.S. Government, its agencies or instrumentalities, and repurchase agreements secured by such obligations or cash. Cash equivalents also include commercial paper and U.S. agency bonds, which are marketable debt securities recorded at fair value and accounted for in the same manner as other marketable debt securities described below.
Short-term Investments	Short-term Investments The Company’s investments in marketable debt securities are classified as available-for-sale and recorded at fair value. Investments with original maturities of greater than three months and remaining maturities of less than one year are classified as short-term investments. Investments with maturities beyond one year may be classified as short-term based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. Short-term investments primarily consist of U.S. agency bonds, commercial paper, corporate bonds, asset-backed securities, and U.S. treasuries. Unrealized gains and losses are included in accumulated other comprehensive income (loss) in stockholders’ equity. Any discount or premium arising at purchase is accreted or amortized to interest income or expense. Realized gains and losses and declines in fair value, if any, judged to be other than temporary are reported in other income (expense), net. When securities are sold, any associated unrealized gain or loss initially recorded as a separate component of stockholders’ equity is reclassified out of stockholders’ equity on a specific-identification basis and recorded in earnings for the period. The Company periodically evaluates whether declines in fair values of its investments below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company’s ability and intent to hold the marketable security until a forecasted recovery occurs. Factors considered include quoted market prices, recent financial results and operating trends, implied values from any recent transactions or offers of investee securities, credit quality of debt instrument issuers, other publicly available information that may affect the value of the marketable security, duration and severity of the decline in value, and management’s strategy and intentions for holding the marketable security. To date, the Company has not recorded any impairment charges on its marketable securities related to other-than-temporary declines in market value.
Fair Value Measurements	Fair Value Measurements Financial assets and liabilities are recorded at fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The hierarchy below lists three levels of fair value based on the extent to which inputs used in measuring fair value are observable in the market. Observable inputs reflect market data obtained from independent sources while unobservable inputs reflect market assumptions made by the reporting entity. The three-level hierarchy for the inputs to valuation techniques used to measure fair value is briefly summarized as follows: Level 1 — Unadjusted quoted prices in active markets that are accessible to the reporting entity at the measurement date for identical assets and liabilities. Level 2 — Inputs other than quoted prices in active markets for identical assets and liabilities that are observable either directly or indirectly for substantially the full term of the asset or liability. Level 2 inputs include the following: • Quoted prices for similar assets and liabilities in active markets. • Quoted prices for identical or similar assets or liabilities in markets that are not active. • Observable inputs other than quoted prices that are used in the valuation of the asset or liabilities (e.g., interest rate and yield curve quotes at commonly quoted intervals). • Inputs that are derived principally from or are corroborated by observable market data by correlation or other means. Level 3 — Unobservable inputs for the assets or liabilities (i.e., supported by little or no market activity). Level 3 inputs include management’s own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk). This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value.
Inventory and Other Deferred Costs	Inventory and Other Deferred Costs Inventory, consisting of supplies used in the Company’s genomic analysis contracts, are valued at the lower of cost or net realizable value. Cost is determined using actual costs, on a first-in, first-out basis. Other deferred costs relate to work in process for costs incurred on genomic analysis contracts that have not been completed or recognized as revenue. Other deferred costs represent materials used in sequencing services, labor, and overhead allocations.
Leases	Leases The Company categorizes leases with contractual terms longer than twelve months as either operating or finance leases. Finance leases are generally those leases that allow the Company to substantially utilize or pay for the entire asset over its estimated life. All other leases are categorized as operating leases. As of June 30, 2021, the Company had no finance leases. Certain lease contracts include obligations to pay for other services, such as maintenance. The Company elected to account for these other services as a component of the lease (i.e., the Company elected the practical expedient not to separate lease and non-lease components). Lease liabilities are recognized at the present value of the fixed lease payments, reduced by landlord incentives, using a discount rate based on the Company’s current borrowing rate at the lease commencement date, adjusted for various factors including level of collateralization and term (the “incremental borrowing rate”), unless the rate implicit in the lease is readily determinable. The current portion of lease liabilities is included in “Accrued and other current liabilities.” Lease assets are recognized based on the initial present value of the fixed lease payments, reduced by landlord incentives, plus any direct costs from executing the leases or lease prepayments reclassified from “Other long-term assets” upon lease commencement. Lease assets are presented as “Operating lease right-of-use assets” as a long-term asset. Leasehold improvements are capitalized at cost and amortized over the lesser of their expected useful life or the lease term. Costs associated with operating lease assets are recognized on a straight-line basis within operating expenses over the term of the lease. The Company has made an accounting policy election not to recognize right-of-use assets and lease liabilities that arise from leases with a term of 12 months or less. Lease payments are recognized as an expense on a straight-line basis over the lease term.
Recent Accounting Pronouncements	Recent Accounting Pronouncements New Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables. The accounting update also made minor changes to the impairment model for available-for-sale debt securities. In November 2019, the FASB delayed the effective date for Topic 326 as applicable to smaller reporting companies to the first quarter of 2023. While the Company will no longer qualify as a smaller reporting company starting in the first quarter of 2022, the delayed effective date still applies to the Company. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements and related disclosures. The Company will apply the new guidance by means of a cumulative-effect adjustment to the opening retained earnings as of the beginning of the first reporting period in which the guidance is effective.
JOBS Act Accounting Election	JOBS Act Accounting Election The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has irrevocably elected not to avail itself of this exemption from new or revised accounting standards, and therefore, the Company will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Schedule of Percentage of Revenue and Accounts Receivables from Customers	For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows: Revenue Accounts Receivable Three Months Ended June 30, Six Months Ended June 30, June 30, 2021 December 31, 2020 2021 2020 2021 2020 VA MVP 62% 76% 63% 76% 11% * Pfizer Inc. 15% 10% 14% * 50% * Merck & Co., Inc. * * * * 12% 59% * Less than 10% of revenue or accounts receivable

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2021
Disaggregation Of Revenue [Abstract]
Schedule of Revenue Disaggregated by Customer Type	The following table presents revenue disaggregated by customer type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 VA MVP $ 13,507 $ 14,750 $ 26,717 $ 29,506 All other customers 8,163 4,745 15,834 9,150 Total revenue $ 21,670 $ 19,495 $ 42,551 $ 38,656

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	6 Months Ended
	Jun. 30, 2021
Balance Sheet Related Disclosures [Abstract]
Schedule of Inventory and Other Deferred Costs	Inventory and other deferred costs consist of the following (in thousands): June 30, December 31, 2021 2020 Raw materials $ 4,225 $ 2,675 Other deferred costs 3,096 2,964 Total inventory and other deferred costs $ 7,321 $ 5,639
Schedule of Accrued and Other Current Liabilities	Accrued and other current liabilities consist of the following (in thousands): June 30, December 31, 2021 2020 Accrued compensation $ 6,219 $ 8,041 Operating lease liabilities 3,360 2,445 Loans—current portion (Note 6) 2,786 — Employee ESPP contributions 462 407 Accrued liabilities 435 313 Accrued taxes 446 95 Total accrued and other current liabilities $ 13,708 $ 11,301

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Assets Measured at Fair Value on Recurring Basis and Level of Inputs used in such Measurements	The following tables show the Company’s financial assets measured at fair value on a recurring basis and the level of inputs used in such measurements as of June 30, 2021 and December 31, 2020 (in thousands): June 30, 2021 Adjusted Cost Unrealized Gains Unrealized Losses Fair Value Fair Value Level Assets Cash and cash equivalents: Cash $ 6,565 $ — $ — $ 6,565 Money market funds 21,523 — — 21,523 Level 1 Commercial paper 41,993 — (1 ) 41,992 Level 2 Total cash and cash equivalents 70,081 — (1 ) 70,080 Short-term investments: Asset-backed securities 18,277 2 (2 ) 18,277 Level 2 Commercial paper 135,889 3 (4 ) 135,888 Level 2 Corporate debt securities 24,377 1 (3 ) 24,375 Level 2 U.S. agency securities 24,056 9 — 24,065 Level 2 U.S. government securities 56,230 4 (12 ) 56,222 Level 2 Total short-term investments 258,829 19 (21 ) 258,827 Total assets measured at fair value $ 328,910 $ 19 $ (22 ) $ 328,907 December 31, 2020 Adjusted Cost Unrealized Gains Unrealized Losses Fair Value Fair Value Level Assets Cash and cash equivalents: Cash $ 4,767 $ — $ — $ 4,767 Money market funds 22,614 — — 22,614 Level 1 Commercial paper 41,145 — (1 ) 41,144 Level 2 Total cash and cash equivalents 68,526 — (1 ) 68,525 Short-term investments: Commercial paper 25,470 — — 25,470 Level 2 Corporate debt securities 29,576 — (8 ) 29,568 Level 2 U.S. agency securities 61,436 31 (1 ) 61,466 Level 2 U.S. government securities 18,260 1 — 18,261 Level 2 Total short-term investments 134,742 32 (9 ) 134,765 Total assets measured at fair value $ 203,268 $ 32 $ (10 ) $ 203,290

Loans (Tables)

Loans (Tables)	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Schedule of Amounts Outstanding	Amounts outstanding under the payment agreements are as follows (in thousands): June 30, December 31, 2021 2020 Principal $ 4,757 $ — Less: unamortized discount (339 ) — Total carrying amount 4,418 — Less: current portion (included in “Accrued and other current liabilities”) (2,786 ) — Long-term portion (included in “Other long-term liabilities”) $ 1,632 $ —

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Schedule of Future Minimum Lease Payments	As of June 30, 2021, the Company’s operating leases had a weighted-average remaining lease term of 5.4 years and a weighted-average discount rate of 10.3%. The Company’s discount rates are based on estimates of its incremental borrowing rate, as the discount rates implicit in the leases cannot be readily determined. Future lease payments under operating leases as of June 30, 2021 were as follows (in thousands): Amount 2021 (remaining six months) $ 1,841 2022 3,318 2023 2,046 2024 2,113 2025 2,181 2026 and thereafter 4,378 Total future minimum lease payments 15,877 Less: imputed interest (3,999 ) Present value of future minimum lease payments 11,878 Less: current portion of operating lease liability (3,360 ) Long-term operating lease liabilities $ 8,518

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Shares of Common Stock Available for Issuance	Shares of common stock available for issuance under the Company’s equity incentive plans as of June 30, 2021 and December 31, 2020 were as follows: June 30, December 31, 2021 2020 Reserved for issuance upon exercise of options outstanding under the 2011 Plan 3,030,494 3,389,711 Reserved for issuance upon exercise or settlement of awards outstanding under the 2019 Plan 3,416,066 2,399,513 Reserved and available for issuance under the 2019 Plan 2,783,091 1,977,069 Reserved for issuance upon exercise or settlement of awards outstanding under the Inducement Plan 185,100 199,300 Reserved and available for issuance under the Inducement Plan 801,900 800,700 Reserved and available for issuance under the ESPP 654,636 320,582 Total number of shares reserved 10,871,287 9,086,875
Summary of Stock Option Activity	A summary of the Company’s stock option activity (excluding performance-based stock option activity summarized further below) under the 2011 Plan, 2019 Plan, and Inducement Plan for the six months ended June 30, 2021 is as follows: Outstanding Options (in thousands, except share and per share data) Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance—December 31, 2020 4,948,306 $ 7.10 6.71 $ 146,044 Options granted 728,306 21.89 Options exercised (384,938 ) 3.64 Options cancelled (66,460 ) 9.99 Balance—June 30, 2021 5,225,214 $ 9.38 6.76 $ 84,982 Options vested and exercisable as of June 30, 2021 3,118,662 $ 5.17 5.29 $ 62,790
Summary of Weighted-average Assumptions Used in Determination of Fair Value of Stock Options	The fair value of stock options was estimated using the following weighted-average assumptions: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Expected term (in years) 5.50 - 6.27 5.50 - 6.08 5.50 - 6.27 5.50 - 6.08 Volatility 69.39 - 69.90% 67.58 - 68.18% 68.06 - 69.90% 61.74 - 68.18% Risk-free interest rate 0.94 - 1.06% 0.36 - 0.44% 0.62 - 1.06% 0.36 - 1.66% Dividend yield –% –% –% –%
Summary of Restricted Stock Units Activity	A summary of the Company’s RSU activity under the 2019 Plan and Inducement Plan for the six months ended June 30, 2021 is as follows: Unvested Restricted Stock Units (in thousands, except share and per share data) Number of Shares Weighted- Average Grant Date Fair Value Aggregate Fair Value Balance—December 31, 2020 619,218 $ 10.41 $ 22,670 RSUs granted 514,496 22.94 RSUs vested (119,981 ) 8.51 2,955 RSUs cancelled (28,287 ) 15.86 Balance—June 30, 2021 985,446 $ 17.03 $ 24,932
Stock Based Compensation Expense by Award Type and Function	The following is a summary of stock-based compensation expense by award type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Stock options $ 2,325 $ 1,259 $ 4,503 $ 2,262 RSUs 1,011 310 1,655 423 ESPP 264 177 499 297 Performance-based stock options — 76 — 89 Total stock-based compensation expense $ 3,600 $ 1,822 $ 6,657 $ 3,071 The following is a summary of stock-based compensation expense by function (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Cost of revenue $ 332 $ 209 $ 620 $ 352 Research and development 900 394 1,628 653 Selling, general and administrative 2,368 1,219 4,409 2,066 Total stock-based compensation expense $ 3,600 $ 1,822 $ 6,657 $ 3,071
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Weighted-average Assumptions Used in Determination of Fair Value of Stock Options	During the six months ended June 30, 2021 and 2020, 57,001 Three and Six Months Ended June 30, 2021 2020 Expected term (in years) 0.49 0.50 Volatility 74.88 % 102.10 % Risk-free interest rate 0.04 % 0.12 % Dividend yield –% –% Grant-date fair value per share $ 8.21 $ 4.29
Performance-Based Stock Option | 2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock Option Activity	A summary of the Company’s performance-based stock option activity under the 2019 Plan for the six months ended June 30, 2021 is as follows: Outstanding Performance-Based Options (in thousands, except share and per share data) Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance—December 31, 2020 421,000 $ 5.10 9.21 $ 13,266 Options granted — Options exercised — Options cancelled — Balance—June 30, 2021 421,000 $ 5.10 8.71 $ 8,504 Options vested and exercisable as of June 30, 2021 421,000 $ 5.10 8.71 $ 8,504
Summary of Weighted-average Assumptions Used in Determination of Fair Value of Stock Options	The Company estimated the fair value of the PSO using a Monte Carlo Model and the following assumptions and estimates: 2020 Performance period (in years) 10.00 Derived service period (in years) 4.55 Volatility 63.60 % Risk-free interest rate 1.02 % Dividend yield –% Estimated fair value per share $ 3.31

Basic and Diluted Net Loss Pe_2

Basic and Diluted Net Loss Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Schedule of Computation of Net Loss per Common Share	The following table sets forth the computation of net loss per common share (in thousands, except share and per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Net loss $ (14,953 ) $ (9,255 ) $ (27,357 ) $ (18,394 ) Weighted-average common shares outstanding—basic and diluted 43,960,794 31,731,628 43,113,195 31,538,329 Net loss per common share—basic and diluted $ (0.34 ) $ (0.29 ) $ (0.63 ) $ (0.58 )
Schedule of Potentially Dilutive Shares Excluded from Computation of Diluted Net Loss per Common Share	The Company incurred net losses in the periods presented, and as a result, potential common shares from stock options, common stock warrants, RSUs, and the assumed release of outstanding shares under the ESPP were not included in the diluted shares used to calculate net loss per share, as their inclusion would have been anti-dilutive. The following table sets forth the potentially dilutive shares excluded from the computation of diluted net loss per common share because their effect was anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Common stock warrants — 127,598 — 127,598 Options to purchase common stock 5,646,214 5,624,766 5,646,214 5,624,766 Unvested RSUs 985,446 629,470 985,446 629,470 ESPP 69,380 95,403 69,380 95,403 Total 6,701,040 6,477,237 6,701,040 6,477,237

Company and Nature of Business

Company and Nature of Business - Additional Information (Details)	6 Months Ended
	Jun. 30, 2021Segment
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of reportable segments	1

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	Jan. 29, 2021	Aug. 14, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts			$ 100,000		$ 100,000		$ 100,000
Bad debt expense					$ 0		$ 0
Dividend yield			0.00%	0.00%	0.00%	0.00%
Dividends					$ 0
Minimum | ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Standard payment terms					90 days
Maximum | ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Period between payment by customer and transfer of promised services					1 year
Recognition period of incremental costs					1 year
Follow-On Equity Offerings
Summary Of Significant Accounting Policies [Line Items]
Number of shares issued	3,950,000	6,578,947
Shares issued price per share	$ 38	$ 19
Proceeds from Issuance or Sale of Equity	$ 141,100,000	$ 117,500,000
Offering costs incurred	$ 300,000	$ 400,000
Underwriters
Summary Of Significant Accounting Policies [Line Items]
Number of shares issued	592,500
Proceeds from Issuance or Sale of Equity	$ 21,200,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Percentage of Revenue and Accounts Receivables from Customers (Details) - Customer	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
VA MVP | Revenue
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	62.00%	76.00%	63.00%	76.00%
VA MVP | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			11.00%
Pfizer Inc. | Revenue
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	15.00%	10.00%	14.00%
Pfizer Inc. | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			50.00%
Merck & Co., Inc. | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			12.00%		59.00%

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Percentage of Revenue and Accounts Receivables from Customers (Parenthetical) (Details)	6 Months Ended
	Jun. 30, 2021
Accounts Receivable | Minimum | Customer
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	10.00%

Revenue - Schedule of Revenue D

Revenue - Schedule of Revenue Disaggregated by Customer Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 21,670	$ 19,495	$ 42,551	$ 38,656
VA MVP
Disaggregation Of Revenue [Line Items]
Revenue	13,507	14,750	26,717	29,506
All Other Customers
Disaggregation Of Revenue [Line Items]
Revenue	$ 8,163	$ 4,745	$ 15,834	$ 9,150

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Disaggregation Of Revenue [Line Items]
Contract liabilities	$ 11.5		$ 11.5		$ 21
Contract liability, revenue recognized	$ 9.8	$ 10.8	$ 18.9	$ 21.5
Customer Concentration Risk | Revenues
Disaggregation Of Revenue [Line Items]
Revenue			7.00%	5.00%
Customer Concentration Risk | Revenues | Maximum | Outside of United States
Disaggregation Of Revenue [Line Items]
Revenue	6.00%	1.00%

Revenue - Additional Informat_2

Revenue - Additional Information (Details 1) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-07-01 $ in Millions	Jun. 30, 2021USD ($)
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 16.8
Remaining performance obligation, expected time of satisfaction	3 months
Maximum
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, remaining performance obligation, optional exemption, remaining duration	1 year

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Inventory and Other Deferred Costs (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Inventory And Other Deferred Costs [Abstract]
Raw materials	$ 4,225	$ 2,675
Other deferred costs	3,096	2,964
Total inventory and other deferred costs	$ 7,321	$ 5,639

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Income Statement [Abstract]
Depreciation and amortization expense	$ 1,400	$ 1,400	$ 2,909	$ 2,815
Accumulated depreciation and amortization	$ 15,900		$ 15,900		$ 14,500

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Accrued compensation	$ 6,219	$ 8,041
Operating lease liabilities	$ 3,360	$ 2,445
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Total accrued and other current liabilities	Total accrued and other current liabilities
Loans—current portion (Note 6)	$ 2,786
Employee ESPP contributions	462	$ 407
Accrued liabilities	435	313
Accrued taxes	446	95
Total accrued and other current liabilities	$ 13,708	$ 11,301

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on Recurring Basis and Level of Inputs used in such Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents, Adjusted Cost	$ 70,080	$ 68,525
Fair Value Measurements Recurring
Assets
Cash and cash equivalents, Adjusted Cost	70,081	68,526
Cash and cash equivalents, Unrealized Losses	(1)	(1)
Cash and cash equivalents, Fair Value	70,080	68,525
Assets, Adjusted Cost	328,910	203,268
Assets, Unrealized Gains	19	32
Assets, Unrealized Losses	(22)	(10)
Assets, Fair Value	328,907	203,290
Fair Value Measurements Recurring | Short-term Investments
Assets
Investments, Adjusted Cost	258,829	134,742
Investments, Unrealized Gains	19	32
Investments, Unrealized Losses	(21)	(9)
Investments, Fair Value	258,827	134,765
Fair Value Measurements Recurring | Money Market Funds | Level 1
Assets
Cash and cash equivalents, Adjusted Cost	21,523	22,614
Cash and cash equivalents, Fair Value	21,523	22,614
Fair Value Measurements Recurring | Cash
Assets
Cash and cash equivalents, Adjusted Cost	6,565	4,767
Cash and cash equivalents, Fair Value	6,565	4,767
Fair Value Measurements Recurring | Commercial Paper | Level 2
Assets
Cash and cash equivalents, Adjusted Cost	41,993	41,145
Cash and cash equivalents, Unrealized Losses	(1)	(1)
Cash and cash equivalents, Fair Value	41,992	41,144
Fair Value Measurements Recurring | Commercial Paper | Level 2 | Short-term Investments
Assets
Investments, Adjusted Cost	135,889	25,470
Investments, Unrealized Gains	3
Investments, Unrealized Losses	(4)
Investments, Fair Value	135,888	25,470
Fair Value Measurements Recurring | Asset-backed Securities | Level 2 | Short-term Investments
Assets
Investments, Adjusted Cost	18,277
Investments, Unrealized Gains	2
Investments, Unrealized Losses	(2)
Investments, Fair Value	18,277
Fair Value Measurements Recurring | Corporate Debt Securities | Level 2 | Short-term Investments
Assets
Investments, Adjusted Cost	24,377	29,576
Investments, Unrealized Gains	1
Investments, Unrealized Losses	(3)	(8)
Investments, Fair Value	24,375	29,568
Fair Value Measurements Recurring | U.S. Agency Securities | Level 2 | Short-term Investments
Assets
Investments, Adjusted Cost	24,056	61,436
Investments, Unrealized Gains	9	31
Investments, Unrealized Losses		(1)
Investments, Fair Value	24,065	61,466
Fair Value Measurements Recurring | U.S. Government Securities | Level 2 | Short-term Investments
Assets
Investments, Adjusted Cost	56,230	18,260
Investments, Unrealized Gains	4	1
Investments, Unrealized Losses	(12)
Investments, Fair Value	$ 56,222	$ 18,261

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details)	6 Months Ended
	Jun. 30, 2021USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unrealized loss position for 12 months or greater on security	$ 0
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-term marketable debt securities maturity period	13 months
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-term marketable debt securities maturity period	21 months
Long-term Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt securities, aggregate cost basis	$ 34,700,000
Debt securities, fair value	$ 34,700,000

Loans - Additional Information

Loans - Additional Information (Details) - Payment Agreement with Financing Entity $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Apr. 30, 2021USD ($)Payment	Jun. 30, 2021USD ($)	Jun. 30, 2021USD ($)
Debt Disclosure [Line Items]
Principal amount		$ 4,757	$ 4,757
Initial present value of payment agreements		5,200	5,200
Interest expense		$ 100	$ 100
Software Licenses and Related Software Maintenance
Debt Disclosure [Line Items]
Principal amount	$ 2,400
Number of equal payments | Payment	3
Noninterest bearing rate	0.00%
Imputed interest rate	7.00%
Computer Hardware and Related Hardware Maintenance
Debt Disclosure [Line Items]
Principal amount	$ 3,100
Number of equal payments | Payment	3
May 2021 | Software Licenses and Related Software Maintenance
Debt Disclosure [Line Items]
Payment of debt	$ 800
May 2022 | Software Licenses and Related Software Maintenance
Debt Disclosure [Line Items]
Payment of debt	800
May 2023 | Software Licenses and Related Software Maintenance
Debt Disclosure [Line Items]
Payment of debt	800
July 2021 | Computer Hardware and Related Hardware Maintenance
Debt Disclosure [Line Items]
Payment of debt	1,040
July 2022 | Computer Hardware and Related Hardware Maintenance
Debt Disclosure [Line Items]
Payment of debt	1,040
July 2023 | Computer Hardware and Related Hardware Maintenance
Debt Disclosure [Line Items]
Payment of debt	$ 1,040

Loans - Schedule of Amounts Out

Loans - Schedule of Amounts Outstanding (Details) - Payment Agreement with Financing Entity $ in Thousands	Jun. 30, 2021USD ($)
Debt Disclosure [Line Items]
Principal	$ 4,757
Less: unamortized discount	(339)
Total carrying amount	4,418
Less: current portion (included in “Accrued and other current liabilities”)	(2,786)
Long-term portion (included in “Other long-term liabilities”)	$ 1,632

Leases - Additional Information

Leases - Additional Information (Details) $ in Millions	1 Months Ended			3 Months Ended		6 Months Ended
	May 31, 2021ft²	Apr. 30, 2020	Aug. 31, 2019	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Feb. 28, 2015ft²
Lessee Lease Description [Line Items]
Area of office space | ft²	14,710							31,280
Lease expiration date	Dec. 31, 2022	Nov. 30, 2027
Operating lease, existence of option to extend	false	true
Operating lease, option to extend	no option to extend the term					an option to extend the term for a period of three years
Operating lease option to extend term		3 years
Operating lease cost				$ 0.7	$ 0.7	$ 1.4	$ 1
Operating leases, weighted-average remaining lease term				5 years 4 months 24 days		5 years 4 months 24 days
Operating leases, weighted-average discount rate				10.30%		10.30%
Cash paid for operating lease liabilities						$ 1.4	0.8
Right-of-use assets obtained in exchange for new operating lease liabilities						$ 1.7	$ 9.8
Co-located Data Center Space
Lessee Lease Description [Line Items]
Lease expiration date			Aug. 31, 2022
Operating lease, existence of option to extend			true
Operating lease, option to extend						an option to extend the term for a period of three years
Operating lease option to extend term			3 years

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Leases [Abstract]
2021 (remaining six months)	$ 1,841
2022	3,318
2023	2,046
2024	2,113
2025	2,181
2026 and thereafter	4,378
Total future minimum lease payments	15,877
Less: imputed interest	(3,999)
Present value of future minimum lease payments	11,878
Less: current portion of operating lease liability	(3,360)	$ (2,445)
Long-term operating lease liabilities	$ 8,518	$ 8,541

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Vesting rate at the end of one year				25.00%
vesting rights description				Options granted to new hires generally vest over a four-year period, with 25% vesting at the end of one year and the remaining vesting monthly thereafter. Options granted as merit awards generally vest monthly over a three- or four-year period.
Closing price of common stock	$ 25.30			$ 25.30
Weighted-average grant date fair value of options granted	$ 12.34		$ 6.70	$ 13.55	$ 4.81
Unrecognized stock-based compensation cost of unvested options	$ 19,000,000			$ 19,000,000
Unrecognized stock-based compensation of unvested options, recognized over weighted-average period				2 years 6 months
Options Granted as Merit Awards | Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				3 years
Options Granted as Merit Awards | Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Closing price of common stock	$ 25.30			$ 25.30
Unrecognized stock-based compensation of unvested options, recognized over weighted-average period				2 years 10 months 24 days
Unrecognized stock-based compensation cost of unvested RSUs	$ 15,600,000			$ 15,600,000
Restricted Stock Units | Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				3 years
Minimum | Restricted Stock Units | Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				3 years
Maximum | Restricted Stock Units | Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based Options granted	3,030,494	3,389,711		3,030,494
2011 Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted in years				10 years
2019 Plan | Performance-Based Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted in years				10 years
Closing price of common stock	$ 25.30			$ 25.30
Unrecognized stock-based compensation cost of unvested options	$ 0			$ 0
Performance-based Options granted	421,000	421,000		421,000
Share based compensation arrangement by share based payment equal to or greater than average market capital		$ 1,000,000,000		$ 1,000,000,000
Average market capitalization threshold satisfaction period		30 days		30 days
Share based compensation arrangement by share based payment award description				The shares subject to the PSO would vest in full if the Company’s average market capitalization is equal to or greater than $1 billion over a 30 calendar day period. Upon a change in control, the vesting of the shares subject to the PSO would accelerate on a pro rata basis based on the price per share in such change in control transaction multiplied by the price per share at such time divided by $1 billion, with up to 100% of the shares eligible for such accelerated vesting.
2019 Plan | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price options granted				100.00%
2019 Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted in years				10 years
2019 Plan | Maximum | Performance-Based Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting rate at the end of one year				100.00%
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of purchase price of common stock				85.00%
Common stock shares purchased				57,001	71,480
Incremental compensation cost				$ 1,200,000
Incremental compensation cost recognized	$ 600,000
2019 Employee Stock Purchase Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of earnings for purchase of common stock at discounted price				15.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Shares of Common Stock Available for Issuance (Details) - shares	Jun. 30, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total number of shares reserved	10,871,287	9,086,875
2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Reserved for issuance upon exercise of options outstanding	3,030,494	3,389,711
2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Reserved for issuance upon exercise or settlement of awards outstanding	3,416,066	2,399,513
Issuance under 2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of stock options reserved for issuance	2,783,091	1,977,069
Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of stock options reserved for issuance	801,900	800,700
Reserved for issuance upon exercise or settlement of awards outstanding	185,100	199,300
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of stock options reserved for issuance	654,636	320,582

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares
2011 Plan, 2019 Plan and Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding Options, Number of Shares, Beginning Balance | shares	4,948,306
Outstanding Options, Number of Shares, granted | shares	728,306
Outstanding Options, Number of Shares, exercised | shares	(384,938)
Outstanding Options, Number of Shares, cancelled | shares	(66,460)
Outstanding Options, Number of Shares, Ending Balance | shares	5,225,214	4,948,306
Options vested and exercisable, Number of Shares | shares	3,118,662
Outstanding Options, Weighted-Average Exercise Price, Beginning Balance | $ / shares	$ 7.10
Outstanding Options, Weighted-Average Exercise Price, granted | $ / shares	21.89
Outstanding Options, Weighted-Average Exercise Price, exercised | $ / shares	3.64
Outstanding Options, Weighted-Average Exercise Price, cancelled | $ / shares	9.99
Outstanding Options, Weighted-Average Exercise Price, Ending Balance | $ / shares	9.38	$ 7.10
Options vested and exercisable, Weighted-Average Exercise Price | $ / shares	$ 5.17
Outstanding Options, Weighted-Average Remaining Contractual Term (in years)	6 years 9 months 3 days	6 years 8 months 15 days
Options vested and exercisable, Weighted-Average Remaining Contractual Term (in years)	5 years 3 months 14 days
Outstanding Options, Aggregate Intrinsic Value | $	$ 84,982	$ 146,044
Options vested and exercisable, Aggregate Intrinsic Value | $	$ 62,790
2019 Plan | Performance-Based Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding Options, Number of Shares, Beginning Balance | shares	421,000
Outstanding Options, Number of Shares, Ending Balance | shares	421,000	421,000
Options vested and exercisable, Number of Shares | shares	421,000
Outstanding Options, Weighted-Average Exercise Price, Beginning Balance | $ / shares	$ 5.10
Outstanding Options, Weighted-Average Exercise Price, Ending Balance | $ / shares	5.10	$ 5.10
Options vested and exercisable, Weighted-Average Exercise Price | $ / shares	$ 5.10
Outstanding Options, Weighted-Average Remaining Contractual Term (in years)	8 years 8 months 15 days	9 years 2 months 15 days
Options vested and exercisable, Weighted-Average Remaining Contractual Term (in years)	8 years 8 months 15 days
Outstanding Options, Aggregate Intrinsic Value | $	$ 8,504	$ 13,266
Options vested and exercisable, Aggregate Intrinsic Value | $	$ 8,504

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Weighted-average Assumptions Used in Determination of Fair Value of Service-Based Stock Options (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Volatility, minimum	69.39%	67.58%	68.06%	61.74%
Volatility, maximum	69.90%	68.18%	69.90%	68.18%
Risk-free interest rate, minimum	0.94%	0.36%	0.62%	0.36%
Risk-free interest rate, maximum	1.06%	0.44%	1.06%	1.66%
Dividend yield	0.00%	0.00%	0.00%	0.00%
2019 Plan | Performance-Based Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)			10 years
Derived service period (in years)			4 years 6 months 18 days
Volatility			63.60%
Risk-free interest rate			1.02%
Estimated fair value per share			$ 3.31
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 months 26 days	6 months	5 months 26 days	6 months
Volatility	74.88%	102.10%	74.88%	102.10%
Risk-free interest rate	0.04%	0.12%	0.04%	0.12%
Estimated fair value per share	$ 8.21	$ 4.29	$ 8.21	$ 4.29
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 6 months	5 years 6 months	5 years 6 months	5 years 6 months
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 3 months 7 days	6 years 29 days	6 years 3 months 7 days	6 years 29 days

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Units - 2019 Plan and Inducement Plan $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested Restricted Stock Units, Number of Shares, Beginning Balance | shares	619,218
Unvested Restricted Stock Units, Number of Shares, granted | shares	514,496
Restricted Stock Units, Number of Shares, vested | shares	(119,981)
Unvested Restricted Stock Units, Number of Shares, cancelled | shares	(28,287)
Unvested Restricted Stock Units, Number of Shares, Ending Balance | shares	985,446
Unvested Restricted Stock Units, Weighted-Average Grant Date Fair Value, Beginning Balance | $ / shares	$ 10.41
Estimated fair value per share | $ / shares	22.94
Restricted Stock Units, Weighted-Average Grant Date Fair Value, vested | $ / shares	8.51
Unvested Restricted Stock Units, Weighted-Average Grant Date Fair Value, cancelled | $ / shares	15.86
Unvested Restricted Stock Units, Weighted-Average Grant Date Fair Value, Ending Balance | $ / shares	$ 17.03
Unvested Restricted Stock Units, Aggregate Fair Value | $	$ 24,932	$ 22,670
Restricted Stock Units, Aggregate Fair Value, vested | $	$ 2,955

Stock-Based Compensation - Su_5

Stock-Based Compensation - Summary of Stock-Based Compensation Expense by Award Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 3,600	$ 1,822	$ 6,657	$ 3,071
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	2,325	1,259	4,503	2,262
Performance-based Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		76		89
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	1,011	310	1,655	423
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 264	$ 177	$ 499	$ 297

Stock-Based Compensation - Su_6

Stock-Based Compensation - Summary of Stock-Based Compensation Expense by Function (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 3,600	$ 1,822	$ 6,657	$ 3,071
Costs of revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	332	209	620	352
Research and development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	900	394	1,628	653
Selling, general, and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,368	$ 1,219	$ 4,409	$ 2,066

Basic and Diluted Net Loss Pe_3

Basic and Diluted Net Loss Per Common Share - Schedule of Computation of Net Loss per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net loss	$ (14,953)	$ (9,255)	$ (27,357)	$ (18,394)
Weighted-average common shares outstanding—basic and diluted	43,960,794	31,731,628	43,113,195	31,538,329
Net loss per common share—basic and diluted	$ (0.34)	$ (0.29)	$ (0.63)	$ (0.58)

Basic and Diluted Net Loss Pe_4

Basic and Diluted Net Loss Per Common Share - Schedule of Potentially Dilutive Shares Excluded from Computation of Diluted Net Loss per Common Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted net loss per share	6,701,040	6,477,237	6,701,040	6,477,237
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted net loss per share	0	127,598	0	127,598
Options To Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted net loss per share	5,646,214	5,624,766	5,646,214	5,624,766
Unvested RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted net loss per share	985,446	629,470	985,446	629,470
ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted net loss per share	69,380	95,403	69,380	95,403