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Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Federal corporate tax rate |  |  | 21.00% |  | 35.00%
Salaries and employee benefits | $ 37,726 | $ 33,503 | $ 74,293 | $ 67,736 |
Other noninterest expense | $ 4,332 | 4,868 | $ 8,747 | 9,397 |
ASU 2018-02 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Reclassification upon ASU implementation |  |  |  |  | $ 0
ASU 2017-07 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Salaries and employee benefits |  | 400 |  | 800 |
Other noninterest expense |  | $ (400) |  | $ (800) |
AOCI [Member] | ASU 2016-01 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Reclassification upon ASU implementation |  |  |  |  | (2,600)
Retained Earnings [Member] | ASU 2016-01 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Reclassification upon ASU implementation |  |  |  |  | 2,600
AOCI [Member] | ASU 2018-02 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Reclassification upon ASU implementation |  |  |  |  | (5,575)
Retained Earnings [Member] | ASU 2018-02 [Member] |  |  |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |  |  |
Reclassification upon ASU implementation |  |  |  |  | $ 5,575

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