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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, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		$ 8,610	$ (22,928)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		1	0
Tax effect	[1]	(1,729)	4,736
Unrealized gains (losses), net of tax		6,880	(18,192)
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		8,610	(22,928)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		(1)	0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax		8,609	(22,928)
Tax effect		(1,729)	4,736
Unrealized gains (losses), net of tax		6,880	(18,192)
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		374	(375)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		0	0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax		374	(375)
Tax effect		0	0
Unrealized gains (losses), net of tax		374	(375)
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		8,236	(22,553)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		(1)	0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax		8,235	(22,553)
Tax effect		(1,729)	4,736
Unrealized gains (losses), net of tax		6,506	(17,817)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses), net of tax		$ 0	$ 0
[1] See “Note 9 – Accumulated Other Comprehensive Income” for tax effect reconciliation.

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Amount, before tax and after adjustment, of 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 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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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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