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, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 323,822	$ 285,784	$ 249,560
Other adjustments	(8,526)	12,308	28,233
Additions charged to costs and expenses	5,353	25,730	7,991
Balance at end of period, noncurrent	$ 320,649	$ 323,822	$ 285,784