Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2022

Fair Value Disclosures [Abstract]

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

The following table provides the assets and liabilities measured at fair value on a recurring basis and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such value at June 30, 2022 and December 31, 2021:

	As of
	June 30, 2022
	Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(in thousands)
Assets:
Cash equivalents:
Money market funds	$	12,299	$	12,299	$	—	$	—
Commercial paper		4,191		—		4,191		—
Total cash equivalents at fair value		16,490		12,299		4,191		—
Short-term investments:
U.S. Treasury securities		4,989		4,989		—		—
U.S. Government agency securities		10,004		10,004		—		—
Commercial paper and corporate bonds		19,220		—		19,220		—
Total short-term investments at fair value		34,213		14,993		19,220		—
Total assets at fair value	$	50,703	$	27,292	$	23,411	$	—

	As of
	December 31, 2021
	Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(in thousands)
Assets:
Money market funds	$	84,102	$	84,102	$	—	$	—
Liabilities:
Contingent earnout	$	524	$	—	$	—	$	524

Schedule of Rollforward of the Estimate Fair Values for Instruments

The following tables present the rollforward of the estimated fair values for instruments classified by the Company within Level 3 of the fair value hierarchy defined above, measured using significant unobservable inputs:

	Warrant liabilities		Forward obligation		Contingent earnout			Total
	(in thousands)
December 31, 2021	$	—	$	—	$	524		$	524
Payment of contingent earnout		—		—		(524	)		(524	)
June 30, 2022	$	—	$	—	$	—		$	—

	Warrant liabilities		Forward obligation		Contingent earnout			Total
	(in thousands)
December 31, 2020	$	1,914	$	2,750	$	930		$	5,594
Payment of contingent earnout		—		—		(681	)		(681	)
Change in fair value		17		150		7			174
June 30, 2021	$	1,931	$	2,900	$	256		$	5,087

Summary of Short-Term Investments

The following table summarizes the Company's short-term investments, considered available-for-sale, as of June 30, 2022. The Company did not hold any short-term investments as of December 31, 2021.

	June 30, 2022
	Fair Value		Cost Basis		Unrealized Losses Recognized in AOCI
Short-term investments:
U.S. Treasury securities	$	4,989	$	4,993	$	(4	)
U.S. Government agency securities		10,004		10,037		(33	)
Commercial paper and corporate bonds		19,220		19,225		(5	)
Total short-term investments at fair value	$	34,213	$	34,255	$	(42	)

Summary of Warrants Issued and Outstanding

Warrants issued and outstanding at December 31, 2021 included the following:

Number of warrants		Exercise price per share
	27,397	$	10.95
	54,793	$	17.80
	249,313	$	20.08
	331,503

Summary of Fair Values Determined Using Black-Scholes Option-Pricing Model

As of June 30, 2021, warrants fully vested and outstanding had estimated fair values ranging from $7.35 to $12.62. Fair values were determined using the Black-Scholes option-pricing model with the following input assumptions for the six months ended June 30, 2021:

	Six Months Ended
	June 30, 2021
Expected volatility range (weighted average)	79.10% to 85.51% (80.38%)
Dividend yield	0.00%
Risk-free interest rates range (weighted average)	0.35% to 1.31% (1.12%)
Expected term range (average)	2.50 years to 8.27 years (6.80 years)