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Equity Incentive Plans - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended
	Feb. 29, 2020	Jul. 31, 2018	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date estimated fair value of options granted			$ 5.27
Net proceeds from stock option exercised			$ 216,000	$ 2,000
Stock-based compensation expenses			$ 2,948,000	$ 1,922,000
Number of shares issued upon vesting of restricted stock units			0	0
Proceeds			$ 375,000	$ 198,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued under ESPP	75,804
Purchase price	$ 4.95
Proceeds	$ 400,000
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted			1,919,789
Number of options exercised			141,551	770
Net proceeds from stock option exercised			$ 200,000	$ 200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted			0	0
Performance-Based Restricted Stock Units (PRSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		903,374	0	0
Number of shares, outstanding			849,328
Number of vested shares			0
Stock-based compensation expenses			$ 900,000	$ 0