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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, 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.

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