Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		$ 12,276		$ (7,229)		$ 289
Reclassification adjustment for net realized (gains) losses included in net income		(6)		0		(142)
Comprehensive income (loss) before income tax (expense) benefit		12,270		(7,229)		147
Tax effect	[1]	(2,458)		1,415		89
Unrealized gains (losses), net of tax		9,812		(5,814)		236
Unrealized Holding Gains (Losses) on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gains (losses) arising during the period		12,276		(7,229)		289
Reclassification adjustment for net realized (gains) losses included in net income		(6)		0		(142)
Comprehensive income (loss) before income tax (expense) benefit		12,270		(7,229)		147
Tax effect	[1]	(2,458)		1,415		89
Unrealized gains (losses), net of tax		9,812		(5,814)		236
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		565		(495)		407
Reclassification adjustment for net realized (gains) losses included in net income		0		0		0
Comprehensive income (loss) before income tax (expense) benefit		565		(495)		407
Tax effect		0	[2]	0	[2]	0	[1]
Unrealized gains (losses), net of tax		565		(495)		407
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		11,711		(6,734)		(118)
Reclassification adjustment for net realized (gains) losses included in net income		(6)		0		(142)
Comprehensive income (loss) before income tax (expense) benefit		11,705		(6,734)		(260)
Tax effect		(2,458)	[2]	1,415	[2]	89	[1]
Unrealized gains (losses), net of tax		$ 9,247		$ (5,319)		$ (171)

[1] (1) See “Note 17 – Accumulated Other Comprehensive Income (Loss)” in the accompanying notes to consolidated financial statements for tax effect reconciliation.

[2] Calculations are based on a federal income tax rate of 21% in 2019 and 2018 and 34% in 2017.