Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		$ 1,971	$ (7,685)	$ (2,602)
OCI before reclassifications	$ (6,931)	7,115	11,810
Amounts reclassified from AOCI	345	105	262
Net unrealized gains (losses)	(6,586)	7,220	12,072
Tax effect	1,280	(1,493)	(2,416)
Unrealized gains (losses), net of tax	(5,306)	5,727	9,656
Tax Cuts and Jobs Act Reclassification to Retained Earnings				223
Ending Balance		7,698	1,971	(7,685)
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		4,612	(5,200)	391
OCI before reclassifications	(7,229)	7,474	12,276
Amounts reclassified from AOCI	0	(71)	(6)
Net unrealized gains (losses)	(7,229)	7,403	12,270
Tax effect	1,415	(1,530)	(2,458)
Unrealized gains (losses), net of tax	(5,814)	5,873	9,812
Tax Cuts and Jobs Act Reclassification to Retained Earnings				223
Ending Balance		10,485	4,612	(5,200)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		54	256	230
OCI before reclassifications	33	(121)	(256)
Amounts reclassified from AOCI	0	0	0
Net unrealized gains (losses)	33	(121)	(256)
Tax effect	(7)	25	54
Unrealized gains (losses), net of tax	26	(96)	(202)
Tax Cuts and Jobs Act Reclassification to Retained Earnings				0
Ending Balance		(42)	54	256
Defined Benefit Pension Plan [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(2,695)	(2,741)	(3,223)
OCI before reclassifications	265	(238)	(210)
Amounts reclassified from AOCI	345	176	268
Net unrealized gains (losses)	610	(62)	58
Tax effect	(128)	12	(12)
Unrealized gains (losses), net of tax	$ 482	(50)	46
Tax Cuts and Jobs Act Reclassification to Retained Earnings				0
Ending Balance		$ (2,745)	$ (2,695)	$ (2,741)

Tax Cuts and Jobs Act, Non-cash Reclassification to Retained Earnings

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 before tax, after 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) allocated to other comprehensive income (loss).

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