Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Investor
Long-term Purchase Commitment [Line Items]
Remaining purchase obligation	$ 1,200		$ 1,200
Amount of related party transaction	1,200	$ 800	3,700	$ 2,400
Remaining purchase obligation	1,200		1,200
Amazon Web Services
Long-term Purchase Commitment [Line Items]
Professional fees	1,500	1,100	4,200	2,600
Remaining purchase obligation	1,400		1,400
Remaining purchase obligation	1,400		1,400
Professional fees	$ 1,500	$ 1,100	$ 4,200	$ 2,600