Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Change in allowance for doubtful accounts	$ 200
Capitalized contract cost, amortization period	5 years
Commission expense	$ 5,300	$ 3,100
Customer Concentration Risk | Sales Revenue, Net | Foreign Customers
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	33.50%	31.90%
Customer Concentration Risk | Sales Revenue, Net | Government Agencies
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	14.90%	17.80%
Customer Concentration Risk | Sales Revenue, Net | Federal Government Agencies
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	6.00%	8.50%