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FDIC Shared-Loss Receivable (Narrative) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Jun. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Dec. 31, 2016
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FDIC Shared-Loss Receivable [Abstract] |  |  |  |  |  |
Loans and Leases Receivable, Gross, Carrying Amount, Covered | $ 58,900 |  |  |  |  |
FDIC shared-loss payable | $ 104,576 | $ 103,487 | $ 101,342 | $ 100,203 | $ 99,126 | $ 97,008

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- Definition FDIC Shared-Loss Receivable [Abstract] + References No definition available. + Details
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- Definition Payable to FDIC for Loss Share Agreements + References No definition available. + Details
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- Definition Aggregate gross carrying amount of loans and leases receivable covered by loss sharing agreements. + References No definition available. + Details
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