Income Taxes - Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of unrecognized tax benefits
Balance at the beginning of the year	$ 0	$ 0	$ 3,088
Additions for prior year tax positions	0	0	4,631
Reductions for prior year tax positions	0	0	(7,719)
Balance at the end of the year	$ 0	$ 0	$ 0