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FDIC Shared-Loss Receivable FDIC Shared-Loss Payable (Changes in Payable to FDIC) (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016
FDIC Shared-Payable [Abstract] |  |  |  |
FDIC shared-loss payable | $ 102,466 | $ 98,013 | $ 101,342 | $ 97,008
Accretion expense | 992 | 954 |  |
Adjustments related to changes in assumptions | $ 132 | $ 51 |  |

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- Definition Amount of accretion expense for FDIC shared-loss payable. + References No definition available. + Details
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- Definition FDIC shared-loss payable adjustments related to changes in assumptions. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition FDIC Shared-Payable [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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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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