Mortgage Banking Activities - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Derivative asset, fair value	$ 2,613	$ 7,620
Derivative liability, fair value	379	4,467
Interest rate lock commitments
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Derivative, notional amount	178,202	398,722
Mandatory forward sales contracts
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Derivative, notional amount	204,500	514,000
Best efforts forward sales contracts
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Derivative, notional amount	$ 17,447	$ 19,803

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