Income Taxes (Components Of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal
Current	$ 10,898	$ 17,444	$ 21,942
Deferred	10,934	(21,947)	(25,594)
Total	21,832	(4,503)	(3,652)
State
Current	955	2,239	943
Deferred	(579)	(56)	(1,203)
Total	376	2,183	(260)
Total, Current	11,853	19,683	22,885
Total, Deferred	10,355	(22,003)	(26,797)
Income tax expense (benefit)	$ 22,208	$ (2,320)	$ (3,912)