Revenue Recognition - Summary of Product Revenue Allowance and Reserve Categories (Detail) - HEPLISAV-B® - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounts Receivable Reserves
Product Revenue Allowance and Revenue Categories [Line Items]
Balance at Beginning of Period	$ 1,272
Provisions related to current period sales	11,042	$ 3,274
Credit or payments made during the period	(9,613)	(2,002)
Balance at End of Period	2,701	1,272
Revenue Reserve Accruals
Product Revenue Allowance and Revenue Categories [Line Items]
Balance at Beginning of Period	1,033
Provisions related to current period sales	6,632	1,308
Credit or payments made during the period	(3,772)	(275)
Balance at Beginning of Period	$ 3,893	$ 1,033