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Commitments and Contingencies - Off Balance Sheet Arrangements (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Total commitments and standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 487,927 | $ 491,306
Commercial lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 231,226 | 238,361
Revolving home equity lines |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 192,813 | 189,971
Undisbursed construction loans |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 49,392 | 46,229
Personal and other lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 12,460 | 14,109
Standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 2,036 | $ 2,636

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