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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		$ (3,545)	$ 6,311
Reclassification adjustment for net (gains) losses included in net income		0	(71)
Tax effect	[1]	742	(1,393)
Unrealized gains (losses), net of tax		(2,782)	4,739
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		(3,545)	6,311
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		(3,545)	6,240
Tax effect		742	(1,393)
Unrealized gains (losses), net of tax		(2,803)	4,847
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		(13)	(393)
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		(13)	(393)
Tax effect		0	0
Unrealized gains (losses), net of tax		(13)	(393)
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		(3,532)	6,704
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		(3,532)	6,633
Tax effect		742	(1,393)
Unrealized gains (losses), net of tax		(2,790)	5,240
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses), net of tax		$ 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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