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Fair Value of Assets and Liabilities - Recorded on a Recurring Basis (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 USD ($) security | Dec. 31, 2016 USD ($) security
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | $ 332,467 | $ 372,580
Derivative financial assets (interest rate contracts) | 74 | 55
Derivative financial liabilities (interest rate contracts) | $ 740 | $ 933
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Number of securities | security | 0 | 0
Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Number of securities | security | 1 |
Assets and liabilities at fair value measured on a recurring basis | Carrying Value | Interest rate contract |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial assets (interest rate contracts) | $ 74 | $ 55
Derivative financial liabilities (interest rate contracts) | 740 | 933
Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate contract |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial assets (interest rate contracts) | 0 | 0
Derivative financial liabilities (interest rate contracts) | 0 | 0
Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Interest rate contract |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial assets (interest rate contracts) | 74 | 55
Derivative financial liabilities (interest rate contracts) | 740 | 933
Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Interest rate contract |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial assets (interest rate contracts) | 0 | 0
Derivative financial liabilities (interest rate contracts) | 0 | 0
Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government agencies | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 188,061 | 253,434
Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government agencies | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government agencies | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 188,061 | 253,434
Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government agencies | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
SBA-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 25,982 | 607
SBA-backed securities | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 25,982 | 607
SBA-backed securities | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
SBA-backed securities | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 25,817 | 0
SBA-backed securities | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 165 | 607
Debentures of government sponsored agencies | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 12,938 | 35,403
Debentures of government sponsored agencies | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Debentures of government sponsored agencies | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 12,938 | 35,403
Debentures of government sponsored agencies | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Privately issued CMOs |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 1,431 | 419
Privately issued CMOs | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 1,431 | 419
Privately issued CMOs | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Privately issued CMOs | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 1,431 | 419
Privately issued CMOs | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Obligations of state and political subdivisions | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 97,491 | 77,701
Obligations of state and political subdivisions | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Obligations of state and political subdivisions | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 97,491 | 77,701
Obligations of state and political subdivisions | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Corporate bonds | Assets and liabilities at fair value measured on a recurring basis | Carrying Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 6,564 | 5,016
Corporate bonds | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | 0
Corporate bonds | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 6,564 | 5,016
Corporate bonds | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Securities available for sale | 0 | $ 0
U.S. government agency obligation collateralized by loans guaranteed by SBA program |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Decrease in unrealized gain (loss) due to transfers to Level 3 | $ 6 |

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