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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Commercial lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | $ 238,361 | $ 224,370
Revolving home equity lines |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | 189,971 | 177,678
Undisbursed construction loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | 46,229 | 35,322
Personal and other lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | 14,109 | 11,758
Standby letters of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | 2,636 | 4,074
Total commitments and standby letters of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loan commitments and standby letters of credit, off-balance sheet | $ 491,306 | 453,202
Percentage of commitments expiring in 2018 | 35.00% |
Percentage of commitments expiring between 2019 and 2025 | 51.00% |
Percentage of commitments expiring 2026 and thereafter | 14.00% |
Total commitments and standby letters of credit | Interest Payable and Other Liabilities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Allowance for off-balance sheet commitments | $ 958 | $ 958

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