Commitments and Contingencies - Schedule of Components Lease Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Operating lease cost	$ 343	$ 474
Variable lease cost	226	296
Total lease cost	$ 569	$ 770
Weighted-average remaining lease term (years)	2 years 7 months 20 days	3 years 7 months 24 days
Weighted-average discount rate	9.25%	9.25%