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Fair Value of Assets and Liabilities (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | $ 695,618,000 |  | $ 692,274,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance |  | $ 0 |
Transfers into Level 3 |  | 0 |
Transfers out of Level 3 |  | 0 |
Total gains or losses [Abstract] |  |  |
Included in net income |  | 0 |
Included in other comprehensive income (loss) |  | 0 |
Purchases, issuances, sales and settlements [Abstract] |  |  |
Purchases |  | 0 |
Issuances |  | 0 |
Sales |  | 0 |
Settlements |  | 0 |
Ending Balance |  | 0 |
Impaired Loans Receivable [Abstract] |  |  |
Carrying amount of loans with a specific allowance | 30,239,000 |  | 34,178,000
Fair value of loans with a specific allowance | 28,898,000 |  | 32,603,000
Specific Allowance | 3,220,000 |  | 3,279,000
Fair Value, Measurements, Recurring [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 695,618,000 |  | 692,274,000
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 96,000 |  | 364,000
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 694,554,000 |  | 690,943,000
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 968,000 |  | 967,000
Fair Value, Measurements, Nonrecurring [Member] |  |  |
Impaired Loans Receivable [Abstract] |  |  |
Carrying amount of loans with a specific allowance | 11,438,000 |  |
Fair value of loans with a specific allowance | 8,478,000 |  |
Specific Allowance | 2,960,000 |  |
U.S. Treasury securities and obligations of U.S. government corporations & agencies |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 190,727,000 |  | 198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies | Fair Value, Measurements, Recurring [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 190,727,000 |  | 198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
U.S. Treasury securities and obligations of U.S. government corporations & agencies | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 190,727,000 |  | 198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
Obligations of states and political subdivisions |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 191,103,000 |  | 192,579,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 967,000 |  |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Total gains or losses [Abstract] |  |  |
Included in net income | 1,000 |  |
Included in other comprehensive income (loss) | 0 |  |
Purchases, issuances, sales and settlements [Abstract] |  |  |
Purchases | 0 |  |
Issuances | 0 |  |
Sales | 0 |  |
Settlements | 0 |  |
Ending Balance | 968,000 |  |
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date | 0 | 0 |
Obligations of states and political subdivisions | Fair Value, Measurements, Recurring [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 191,103,000 |  | 192,579,000
Obligations of states and political subdivisions | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
Obligations of states and political subdivisions | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 190,135,000 |  | 191,612,000
Obligations of states and political subdivisions | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 968,000 |  | 967,000
Residential Mortgage-backed Securities [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 311,484,000 |  | 298,672,000
Residential Mortgage-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 311,484,000 |  | 298,672,000
Residential Mortgage-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
Residential Mortgage-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 311,484,000 |  | 298,672,000
Residential Mortgage-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
Trust preferred securities |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 0 | 2,548,000 |
Transfers into Level 3 | 0 | 0 |
Transfers out of Level 3 | 0 | 0 |
Total gains or losses [Abstract] |  |  |
Included in net income | 0 | 0 |
Included in other comprehensive income (loss) | 0 | 18,000 |
Purchases, issuances, sales and settlements [Abstract] |  |  |
Purchases | 0 | 0 |
Issuances | 0 | 0 |
Sales | 0 | 0 |
Settlements | 0 | (44,000) |
Ending Balance | 0 | 2,522,000 |
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date | 0 | $ 0 |
Other securities |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 2,304,000 |  | 2,374,000
Other securities | Fair Value, Measurements, Recurring [Member] |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 2,304,000 |  | 2,374,000
Other securities | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 96,000 |  | 364,000
Other securities | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 2,208,000 |  | 2,010,000
Other securities | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Available-for-sale: [Abstract] |  |  |
Total available-for-sale securities | 0 |  | 0
Impaired Loans (Collateral Dependent) [Member] | Fair Value, Measurements, Nonrecurring [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Assets, Fair Value Disclosure | 8,478,000 |  | 16,437,000
Impaired Loans (Collateral Dependent) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Assets, Fair Value Disclosure | 0 |  | 0
Impaired Loans (Collateral Dependent) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Assets, Fair Value Disclosure | 0 |  | 0
Impaired Loans (Collateral Dependent) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Assets, Fair Value Disclosure | $ 8,478,000 |  | $ 16,437,000

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