Restricted Net Assets (Details) - PRC - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Restricted net assets
Minimum required percentage of statutory reserves	10.00%	10.00%
Percentage of statutory reserves to respective registered capital	50.00%	50.00%
Statutory reserves	$ 0	$ 0
Restricted amount by subsidiaries	$ 306,010	$ 306,010	$ 205,858