Schedule II - Valuation and Qualifying Accounts (Details) - Valuation Allowance of Deferred Tax Assets - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 136,934	$ 118,560	$ 83,251
Additions (Credited) Charged to Expense	(15,311)	21,496	54,421
Write-offs	(313)	(3,122)	(19,112)
Balance at End of Period	$ 121,310	$ 136,934	$ 118,560