Stock Based Awards (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

Activity under the Company’s stock option plan is set forth below:

						Weighted
						Average
				Weighted		Remaining		Aggregate
				Average		Contractual		Intrinsic
	Number of			Exercise		Life		Value
	Shares			Price		(in years)		(in thousands)
Balances, January 1, 2021		2,173,776		$	9.59
Options granted		511,950			6.10
Options cancelled		(67,131	)		10.40
Options exercised		(77,858	)		3.32
Balances, March 31, 2021		2,540,737		$	9.06		6.5	$	7,446
Outstanding and expected to vest as of March 31, 2021		2,357,071		$	9.23		6.3	$	7,332
Exercisable as of March 31, 2021		1,581,920		$	10.36		4.8	$	6,833

Summary of Fair Value of Employee Stock Options

The fair value of employee stock options was estimated using the Black-Scholes model with the following weighted-average assumptions:

	March 31,			March 31,
	2021			2020
Expected volatility		113.5	%		111.0	%
Risk-free interest rate		0.6	%		1.6	%
Dividend yield		0.0	%		0.0	%
Expected life (in years)		6.1			6.1