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Basis of Presentation And Summary Of Significant Accounting Policies (Summary Of Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2018 | Sep. 30, 2017
Supplemental information: |  |
Cash paid for interest | $ 19,803 | $ 10,189
Cash paid for income taxes | 3,790 | 8,677
Noncash investing and financing activities: |  |
Real estate and other assets acquired in settlement of loans | 596 | 379
Accrued and declared unpaid dividends | 4,187 | 3,637
Increase in net unsettled security purchases |  | 75
Assets acquired and liabilities assumed in business combinations: |  |
Fair value of assets acquired | 2,561 | 812
Fair value of liabilities assumed | $ 128 | $ 44

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