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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		$ (50,015)	$ (8,371)	$ 7,474
Reclassification adjustment for net realized (gains) losses included in net income		0	0	(71)
Comprehensive income (loss) before income tax (expense) benefit		(50,015)	(8,371)	7,403
Tax effect	[1]	10,314	1,759	(1,530)
Unrealized gains (losses), net of tax		(39,701)	(6,612)	5,873
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		(50,015)	(8,371)	7,474
Reclassification adjustment for net realized (gains) losses included in net income		0	0	(71)
Comprehensive income (loss) before income tax (expense) benefit		(50,015)	(8,371)	7,403
Tax effect		10,314	1,759	(1,530)
Unrealized gains (losses), net of tax		(39,701)	(6,612)	5,873
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) arising during the period		(900)	5	118
Reclassification adjustment for net realized (gains) losses included in net income		0	0	0
Comprehensive income (loss) before income tax (expense) benefit		(900)	5	118
Tax effect		0	0	0
Unrealized gains (losses), net of tax		(900)	5	118
Unrealized Holding Gains (Losses) on AFS Securities [Member] | All Other AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		(49,115)	(8,376)	7,356
Reclassification adjustment for net realized (gains) losses included in net income		0	0	(71)
Comprehensive income (loss) before income tax (expense) benefit		(49,115)	(8,376)	7,285
Tax effect		10,314	1,759	(1,530)
Unrealized gains (losses), net of tax		$ (38,801)	$ (6,617)	$ 5,755
[1] See “Note 16 – Accumulated Other Comprehensive Income (Loss)” in the accompanying notes to consolidated financial statements 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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