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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) on AFS securities arising during the period		$ (22,815)	$ (1,690)	$ (56,413)	$ (4,247)
Tax effect	[1]	4,788	353	11,687	894
Unrealized gains (losses), net of tax		(18,027)	(1,337)	(44,726)	(3,311)
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		(22,815)	(1,690)	(56,413)	(4,247)
Tax effect		4,788	353	11,687	894
Unrealized gains (losses), net of tax		(18,027)	(1,337)	(44,726)	(3,353)
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		(18)	(14)	(763)	9
Tax effect		0	0	0	0
Unrealized gains (losses), net of tax		(18)	(14)	(763)	9
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		(22,797)	(1,676)	(55,650)	(4,256)
Tax effect		4,788	353	11,687	894
Unrealized gains (losses), net of tax		(18,009)	(1,323)	(43,963)	(3,362)
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, 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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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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