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Summary of Significant Accounting Policies - Dividend (Details) - USD ($) $ / shares in Units, $ in Thousands | Oct. 28, 2016 | Oct. 18, 2016 | Sep. 30, 2016 | Dec. 31, 2015 | Sep. 30, 2015
--- | --- | --- | --- | --- | ---
Cash dividend declared (per share) |  | $ 0.01 |  |  |
Deposits. |  |  | $ 1,777,382 | $ 1,759,086 |
Loans |  |  | $ 1,202,852 | $ 1,133,715 | $ 1,132,912
Subsequent Event | Talmer |  |  |  |  |
Deposits. | $ 48,900 |  |  |  |
Loans | $ 223,400 |  |  |  |

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