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Accumulated Other Comprehensive Income (Loss) (Changes in AOCI by component) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 8,367	$ 767	$ 1,971	$ (7,685)
OCI before reclassifications	46	(1,687)	(8,159)	(12,309)
Amounts reclassified from AOCI	0	(6)	(71)	(6)
Other Comprehensive Income (Loss), before Tax	(46)	1,681	8,088	12,303
Tax effect	54	(302)	(1,684)	(2,472)
Unrealized gains (losses), net of tax	8	1,379	6,404	9,831
Ending Balance	8,375	2,146	8,375	2,146
Unrealized Holding Gains (Losses) on AFS Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	11,139	3,417	4,612	(5,200)
OCI before reclassifications	66	(1,724)	(8,304)	(12,554)
Amounts reclassified from AOCI	0	(6)	(71)	(6)
Other Comprehensive Income (Loss), before Tax	(66)	1,718	8,233	12,548
Tax effect	58	(310)	(1,714)	(2,523)
Unrealized gains (losses), net of tax	(8)	1,408	6,519	10,025
Ending Balance	11,131	4,825	11,131	4,825
Defined Benefit Pension Plan [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(2,695)	(2,741)	(2,695)	(2,741)
OCI before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	0	0
Other Comprehensive Income (Loss), before Tax	0	0	0	0
Tax effect		0	0	0
Unrealized gains (losses), net of tax	0	0	0	0
Ending Balance	(2,695)	(2,741)	(2,695)	(2,741)
Gain (Loss) on Derivative Instruments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(77)	91	54	256
OCI before reclassifications	(20)	37	145	245
Amounts reclassified from AOCI	0	0	0	0
Other Comprehensive Income (Loss), before Tax	20	(37)	(145)	(245)
Tax effect	(4)	8	30	51
Unrealized gains (losses), net of tax	16	(29)	(115)	(194)
Ending Balance	(61)	62	(61)	62
Auction Rate Money Market Preferred Stocks [Member] | Unrealized Holding Gains (Losses) on AFS Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Unrealized gains (losses), net of tax	$ 215	$ 240	$ 75	$ 535

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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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