Stock-Based Compensation - Schedule of Stock-Based Compensation Cost (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	$ 2,331	$ 1,778
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	1,864	1,693
Restricted Stock Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	397
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	70	85
Cost of Sales
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	54	64
Research and Development Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	946	591
Selling, General, and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense recognized	$ 1,331	$ 1,123