Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Federal Income Tax Carry Back to Prior Years	$ 199,000
Operating Loss Carryforwards	11,000
Tax Credit Carryforward, Amount	3,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 22,137	$ 0	$ 0
Tax Year 2011 [Member]
Operating Loss Carryforwards [Line Items]
Income Tax Examination, Year under Examination	2011
Tax Year 2013 [Member]
Operating Loss Carryforwards [Line Items]
Income Tax Examination, Year under Examination	2013