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Basis of Presentation and Summary of Significant Accounting Policies (Summary of Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Supplemental information: |  |
Cash paid for interest | $ 8,418 | $ 8,524
Cash paid for income taxes | 1,000 | 1,248
Noncash investing and financing activities: |  |
Real estate and other assets acquired in settlement of loans | 646 |
Accrued and declared unpaid dividends | $ 4,259 | 4,350
Decrease in net unsettled security purchases |  | $ 1,473

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