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Commitments and Contingencies - Off Balance Sheet Arrangements (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Total commitments and standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 481,698 | $ 491,306
Commercial lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 239,465 | 238,361
Revolving home equity lines |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 190,230 | 189,971
Undisbursed construction loans |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 40,101 | 46,229
Personal and other lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 9,888 | 14,109
Standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 2,014 | $ 2,636

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