Stock-Based Compensation - Summary of Total Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	$ 9,836	$ 9,016
2011 And 2013 Stock Incentive Plan
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	9,836	9,016
Cost of revenue | 2011 And 2013 Stock Incentive Plan
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	739	915
Sales and marketing | 2011 And 2013 Stock Incentive Plan
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	1,938	1,754
Engineering and development | 2011 And 2013 Stock Incentive Plan
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	1,092	1,333
General and administrative | 2011 And 2013 Stock Incentive Plan
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items]
Stock-based compensation expense	$ 6,067	$ 5,014