Income Taxes (Schedule Of Federal And State And Foreign Income Tax Provision) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal, current	$ 158,411	$ 159,774	$ 155,273
State, current	10,500	7,756	8,744
Foreign, current	5,137	5,224	5,254
Current federal, state and foreign income tax	174,048	172,754	169,271
Federal, deferred	788	(5,343)	1,667
State, deferred	(168)	1,414	11
Deferred income tax expense (benefit)	620	(3,929)	1,678
Total income taxes	$ 174,668	$ 168,825	$ 170,949

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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