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FHLB Advances, Other Borrowings and Junior Subordinated Notes (Composition of Borrowed Funds) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 217,917,000 | $ 69,680,000
Borrowed Funds, Average Balance | $ 140,083,000 | $ 50,945,000
Borrowed funds, interest rate during period | 3.14% | 6.03%
Long-term borrowings |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 180,907,000 | $ 49,092,000
Short-term borrowings |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | 37,010,000 | 20,588,000
Federal funds purchased |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | 0 | 0
Borrowed Funds, Average Balance | $ 66,000 | $ 178,000
Borrowed funds, interest rate during period | 1.22% | 0.92%
FHLB advances |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 183,500,000 | $ 33,578,000
Borrowed Funds, Average Balance | $ 105,276,000 | $ 14,485,000
Borrowed funds, interest rate during period | 1.40% | 0.97%
Line of credit |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 10,000 | $ 1,010,000
Borrowed Funds, Average Balance | $ 328,000 | $ 2,079,000
Borrowed funds, interest rate during period | 3.64% | 3.26%
Other borrowings |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 675,000 | $ 2,590,000
Borrowed Funds, Average Balance | $ 1,241,000 | $ 1,739,000
Borrowed funds, interest rate during period | 14.50% | 7.64%
Subordinated notes payable |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 23,713,000 | $ 22,498,000
Borrowed Funds, Average Balance | $ 23,161,000 | $ 22,467,000
Borrowed funds, interest rate during period | 6.93% | 7.13%
Junior subordinated notes |  |
Composition of Borrowed Funds [Line Items] |  |
Borrowed funds | $ 10,019,000 | $ 10,004,000
Borrowed Funds, Average Balance | $ 10,011,000 | $ 9,997,000
Borrowed funds, interest rate during period | 11.11% | 11.07%

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