Income Taxes (Schedule of Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current Expense, Domestic	$ 179,150	$ 258,337	$ 116,802
Deferred Expense (Benefit), Domestic	31,145	28,029	47,370
Domestic, Total	210,295	286,366	164,172
Current Expense, Foreign	(2,318)	12,969	22,362
Deferred Expense (Benefit), Foreign	19,946	3,258	7,053
Foreign, Total	17,628	16,227	29,415
Current Expense, Total	176,832	271,306	139,164
Deferred Expense (Benefit), Total	51,091	31,287	54,423
Total expense	227,923	302,593	193,587
Income (Loss) from Continuing Operations before Income Taxes, Domestic	689,000	910,000	598,000
Income (Loss) from Continuing Operations before Income Taxes, Foreign	$ 43,000	$ 42,000	$ 101,000