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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, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		$ 7,474	$ 12,276	$ (7,229)
Reclassification adjustment for net realized (gains) losses included in net income		(71)	(6)	0
Comprehensive income (loss) before income tax (expense) benefit		7,403	12,270	(7,229)
Tax effect	[1]	(1,530)	(2,458)	1,415
Unrealized gains (losses), net of tax		5,873	9,812	(5,814)
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		7,474	12,276	(7,229)
Reclassification adjustment for net realized (gains) losses included in net income		(71)	(6)	0
Comprehensive income (loss) before income tax (expense) benefit		7,403	12,270	(7,229)
Tax effect	[1]	(1,530)	(2,458)	1,415
Unrealized gains (losses), net of tax		5,873	9,812	(5,814)
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		118	565	(495)
Reclassification adjustment for net realized (gains) losses included in net income		0	0	0
Comprehensive income (loss) before income tax (expense) benefit		118	565	(495)
Tax effect		0	0	0	[1]
Unrealized gains (losses), net of tax		118	565	(495)
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		7,356	11,711	(6,734)
Reclassification adjustment for net realized (gains) losses included in net income		(71)	(6)	0
Comprehensive income (loss) before income tax (expense) benefit		7,285	11,705	(6,734)
Tax effect		(1,530)	(2,458)	1,415	[1]
Unrealized gains (losses), net of tax		$ 5,755	$ 9,247	$ (5,319)
[1] See “Note 17 – 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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