Income Taxes (Schedule Of Components Of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
U.S. federal, Current	$ 90,390	$ 89,154	$ 116,753
State and local, Current	10,223	7,735	9,457
Current, income tax expense (benefit)	100,613	96,889	126,210
U.S. federal, Deferred	3,220	12,190	(2,036)
State and local, Deferred	2,116	1,427	(23)
Deferred, income tax expense (benefit)	5,336	13,617	(2,059)
U.S. federal, Total	93,610	101,344	114,717
State and local, Total	12,339	9,162	9,434
Total income tax expense	$ 105,949	$ 110,506	$ 124,151