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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		$ (66)	$ 1,724	$ 8,304	$ 12,554
Reclassification adjustment for net (gains) losses included in net income		0	(6)	(71)	(6)
Tax effect	[1]	58	(310)	(1,714)	(2,523)
Unrealized gains (losses), net of tax		8	1,379	6,404	9,831
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		(66)	1,724	8,304	12,554
Reclassification adjustment for net (gains) losses included in net income		0	(6)	(71)	(6)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent		(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
Unrealized Holding Gains (Losses) on AFS Securities [Member] | Auction Rate Money Market Preferred and Preferred Stocks [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		215	240	75	535
Reclassification adjustment for net (gains) losses included in net income		0	0	0	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent		215	240	75	535
Tax effect		0	0	0	0
Unrealized gains (losses), net of tax		215	240	75	535
Unrealized Holding Gains (Losses) on AFS Securities [Member] | All Other AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		(281)	1,484	8,229	12,019
Reclassification adjustment for net (gains) losses included in net income		0	(6)	(71)	(6)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent		(281)	1,478	8,158	12,013
Tax effect		58	(310)	(1,714)	(2,523)
Unrealized gains (losses), net of tax		(223)	1,168	6,444	9,490
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses), net of tax		$ 0	$ 0	$ 0	$ 0
[1] See “Note 10 – Accumulated Other Comprehensive Income” for tax effect reconciliation.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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

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