Income Taxes - Deferred Tax Asset Valuation Allowance Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Beginning balance	$ 126,321	$ 127,294	$ 136,766
Net change in valuation allowance	(102,014)	(973)	(5,107)
Ending balance	24,307	126,321	127,294
Impact of Adoption
Deferred Tax Asset, Valuation Allowance [Roll Forward]
Beginning balance	$ 0	0	(4,365)
Ending balance		$ 0	$ 0