Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Other Adjustments	$ 60	$ 1,025
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of Period	235,339	257,728	$ 162,588
Other Adjustments	(12,419)	(62,791)	(4,913)
Additions Charged to Cost and Expense	26,640	40,402	100,053
Balance at End of Period Noncurrent	$ 249,560	$ 235,339	$ 257,728