Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands		9 Months Ended
	Jan. 01, 2020 USD ($)	Sep. 30, 2020 USD ($) Customer	Sep. 30, 2019 USD ($) Customer	Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable including unbilled receivables		$ 5,700		$ 4,000
Concentration risk, number of customer | Customer		1	1
Advertising expenses		$ 9,000	$ 9,000
Accumulated deficit		$ (299,190)		$ (274,549)
Cumulative Effect, Period of Adoption, Adjustment | Revision of Prior Period, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit	$ (400)
Customer Concentration Risk | Revenue
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		15.00%	13.00%
Customer Concentration Risk | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		20.00%
ASU 2016-13
Summary Of Significant Accounting Policies [Line Items]
Increase in the allowance for credit losses	$ 400
ASU 2018-07
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2020
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]		true
ASU 2018-15
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2020
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]		true
ASU 2019-12
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2019
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]		true
Minimum
Summary Of Significant Accounting Policies [Line Items]
Account receivable payment terms		Due immediately
Maximum
Summary Of Significant Accounting Policies [Line Items]
Account receivable payment terms		Due within 60 days