Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Benefit, Continuing Operations, Adjustment of Deferred Tax (Asset) Liability		$ 15,000
Statutory federal income tax rate	35.00%
Income before income tax, Domestic	$ 321,000	497,000	$ 917,000
Unrecognized tax benefits	$ 9,488	$ 0	$ 0	$ 0