Segment Reporting - Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue by geographic area
Total revenue	$ 25,009	$ 24,921	$ 28,330	$ 23,647	$ 23,462	$ 30,033	$ 48,847	$ 50,573	$ 101,907	$ 152,915	$ 114,617
United States | Reportable Geographical Components
Revenue by geographic area
Total revenue									10,114	64,966	27,093
Rest of World | Reportable Geographical Components
Revenue by geographic area
Total revenue									$ 91,793	$ 87,949	$ 87,524