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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		$ 988	$ 2,059	$ (2,557)	$ 8,370
Reclassification adjustment for net (gains) losses included in net income		0	0	0	(71)
Tax effect	[1]	(201)	(379)	541	(1,772)
Unrealized gains (losses), net of tax		808	1,657	(1,974)	6,396
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		988	2,059	(2,557)	8,370
Reclassification adjustment for net (gains) losses included in net income				0	(71)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent				(2,557)	8,299
Tax effect		(201)	(379)	541	(1,772)
Unrealized gains (losses), net of tax		787	1,680	(2,016)	6,527
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		36	253	23	(140)
Reclassification adjustment for net (gains) losses included in net income				0	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent				23	(140)
Tax effect		0	0	0	0
Unrealized gains (losses), net of tax		36	253	23	(140)
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		952	1,806	(2,580)	8,510
Reclassification adjustment for net (gains) losses included in net income				0	(71)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent				(2,580)	8,439
Tax effect		(201)	(379)	541	(1,772)
Unrealized gains (losses), net of tax		751	1,427	(2,039)	6,667
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, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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