Summary of Significant Accounting Policies - Segments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Accounting Policies [Abstract]
Number of reportable segments | segment			1
Number of operating segments | segment			1
Disaggregation of Revenue [Line Items]
Revenue	$ 14,049	$ 16,317	$ 30,870	$ 31,308
United States
Disaggregation of Revenue [Line Items]
Revenue	13,221	15,019	28,518	28,469
International
Disaggregation of Revenue [Line Items]
Revenue	$ 828	$ 1,298	$ 2,352	$ 2,839