Equity Incentive Plan - Schedule of Additional Information on Stock Option Grants And Vesting (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
2016 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of stock options granted	$ 2,492	$ 3,473
Total fair value of options vested	1,439	$ 1,924
2019 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of stock options granted	$ 974