Income Taxes (Summary Of Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal									$ 16,599	$ 16,636	$ 16,846
State									2,478	2,560	2,413
Total current tax expense									19,077	19,196	19,259
Total deferred tax expense									2,640	4,939	(1,244)
Income tax expense	$ 4,565	$ 5,098	$ 4,732	$ 7,322	$ 6,319	$ 6,193	$ 5,813	$ 5,810	$ 21,717	$ 24,135	$ 18,015