Equity Incentive Plan - Stock Based Compensation Expense Included In Consolidated Statements of Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 3,435	$ 2,265
Cost of Revenues [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	1,336	573
General and administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	1,198	1,161
Research and development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	268	87
Sales and Marketing [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 633	$ 444