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Commitments and Contingencies - Off Balance Sheet Arrangements (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Total commitments and standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 610,754 | $ 529,132
Commercial lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 309,469 | 287,533
Revolving home equity lines |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 199,332 | 189,035
Undisbursed construction loans |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 89,605 | 41,033
Personal and other lines of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | 10,431 | 9,567
Standby letters of credit |  |
Other Commitments [Line Items] |  |
Total commitments and standby letters of credit | $ 1,917 | $ 1,964

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