Income Taxes (Schedule Of Provision For Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Current, U.S. federal	$ 58,602	$ 36,779	$ 23,934
Current, U.S. state and local	15,950	7,078	4,484
Current, Foreign	539	600	452
Deferred, U.S. federal, state and local	1,456	(2,773)	5,185
Deferred, Foreign	(23)	2	1
Income tax provision	$ 76,524	$ 41,686	$ 34,056