Income Taxes (Components Of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Federal
Current	$ 69,554	$ 18,109	$ 14,190
Deferred	12,340	40,413	(39,244)
Total	81,894	58,522	(25,054)
State
Current	1,172	(1,430)	1,982
Deferred	828	890	(1,815)
Total	2,000	(540)	167
Current	70,726	16,679	16,172
Deferred	13,168	41,303	(41,059)
Income tax expense (benefit)	$ 83,894	$ 57,982	$ (24,887)