Change in Accumulated Other Comprehensive Income (Changes To Accumulated Other Comprehensive Income By Components) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 1,482	$ (1,553)
Other comprehensive income (loss) before reclassifications	3,565	2,137
Reclassification adjustments	0	3
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax	0	1
Tax effect of current period changes	(749)	(450)
Total other comprehensive income	2,816	1,690
Ending balance	4,298	137
Unrealized Gains And Losses On Available For Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,438	(1,597)
Other comprehensive income (loss) before reclassifications	3,565	2,137
Reclassification adjustments	0	3
Tax effect of current period changes	(749)	(450)
Total other comprehensive income	2,816	1,690
Ending balance	4,254	93
Change In Benefit Obligations And Plan Assets For The Post Retirement Benefit Plan [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	44	44
Ending balance	$ 44	$ 44

Other Comprehensive Income (Loss), Tax Effect Of Current Period Changes

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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