Income Taxes - Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member] - 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	$ 427,030	$ 437,149	$ 285,784
Other adjustments	23,132	(10,957)	8,626
Additions charged to costs and expenses	53,697	838	142,739
Balance at end of period, noncurrent	$ 503,859	$ 427,030	$ 437,149