Income Taxes - Rollforward of Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Roll forward of valuation allowance:
Balance at Beginning of the Year	$ 40,182
Balance at the End of the Year	60,009	$ 40,182
Valuation Allowance of Deferred Tax Assets
Roll forward of valuation allowance:
Balance at Beginning of the Year	40,182	40,278	$ 76,050
Charged (Credited) to Expense	33,509	9,404	(27,186)
Other Additions	0	0	0
Other Deductions	(13,682)	(9,500)	(8,586)
Balance at the End of the Year	$ 60,009	$ 40,182	$ 40,278