Segment Information - Geographic region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Information
Total revenue	$ 14,649	$ 12,451	$ 11,050	$ 13,196	$ 14,946	$ 13,194	$ 12,914	$ 14,257	$ 51,346	$ 55,311	$ 71,857
United States
Segment Information
Total revenue									51,124	55,273	70,319
Europe
Segment Information
Total revenue									$ 222	$ 38	$ 1,538