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FHLB Advances and Other Borrowings (Schedule of Issuance of Subordinated Debentures) (Details) - USD ($) |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 15, 2005 | May 06, 2005 | Mar. 26, 2003 | Dec. 31, 2018 | Dec. 31, 2017
LIBOR |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage over variable rate |  |  |  | 1.75% |
ACB Trust I |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Date of Issuance |  | May 06, 2005 |  |  |
Issuance Amount |  | $ 5,155,000 |  |  |
Carrying Amount at December 31, 2018 |  |  |  | $ 3,646,000 |
Variable Rate |  | 90 day LIBOR + 2.15% |  |  |
Rate as of December 31 |  |  |  | 4.95% | 3.84%
Maturity Date |  | May 31, 2035 |  |  |
ACB Trust I | LIBOR |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage over variable rate |  | 2.15% |  |  |
ACB Trust II |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Date of Issuance | Jul. 15, 2005 |  |  |  |
Issuance Amount | $ 3,093,000 |  |  |  |
Carrying Amount at December 31, 2018 |  |  |  | $ 2,129,000 |
Variable Rate | 90 day LIBOR + 1.85% |  |  |  |
Rate as of December 31 |  |  |  | 4.50% | 3.30%
Maturity Date | Jul. 31, 2035 |  |  |  |
ACB Trust II | LIBOR |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage over variable rate | 1.85% |  |  |  |
RIVR Statutory Trust 1 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Date of Issuance |  |  | Mar. 26, 2003 |  |
Issuance Amount |  |  | $ 7,217,000 |  |
Carrying Amount at December 31, 2018 |  |  |  | $ 5,712,000 |
Variable Rate |  |  | 3-Month LIBOR + 3.15% |  |
Rate as of December 31 |  |  |  | 5.97% | 4.82%
Maturity Date |  |  | Mar. 31, 2033 |  |
RIVR Statutory Trust 1 | LIBOR |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage over variable rate |  |  | 3.15% |  |

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