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Commitments and Contingencies - Off Balance Sheet Arrangements (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Total commitments and standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 567,514 | $ 529,132
Commercial lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 301,107 | 287,533
Revolving home equity lines |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 193,364 | 189,035
Undisbursed construction loans |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 59,548 | 41,033
Personal and other lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 10,923 | 9,567
Standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 2,572 | $ 1,964

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