Federal Income Taxes (Schedule Of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2017	[1]	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal Income Taxes [Abstract]
Tax provision at statutory rate (34%)										$ 3,252	$ 3,192	$ 4,241
Income on tax-exempt loans and securities										(2,056)	(1,751)	(1,566)
Nondeductible interest expense relating to carrying tax-exempt obligations										32	24	22
Revaluation of deferred tax assets										2,291
Dividends received exclusion												(2)
Income from bank owned life insurance										(171)	(210)	(182)
Life insurance proceeds												(35)
Change in valuation allowance												(200)
Stock option compensation										55	30	25
Other, net										162	17	(32)
Income tax provision	$ 1,048		$ 774	$ 950	$ 793	$ 104	$ 383	$ 130	$ 685	$ 3,565	$ 1,302	$ 2,271
Effective income tax rate										62.10%	13.90%	18.20%
Statutory rate										34.00%	34.00%	34.00%

[1] Includes $2.3 million for revaluation of the net deferred tax assets