SBA Loan Servicing Activities - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Servicing Asset at Amortized Cost [Line Items]
Principal balance of SBA loans, excluding PPP loans	$ 300,415	$ 253,330
Principal balance of SBA loans, excluding PPP loans, guaranteed portion	171,548	110,196
Unpaid principal balances of SBA loans serviced for others	$ 459,670	$ 524,910
Servicing assets, weighted average discount rate (in percentage)	12.13%	11.75%
Servicing assets, weighted average prepayment speed (in percentage)	10.37%	10.34%
PPP and Government Loans
Servicing Asset at Amortized Cost [Line Items]
Gain on sale of loans	$ 18,024	$ 1,652
SBA Loan
Servicing Asset at Amortized Cost [Line Items]
Gain on sale of loans	4,207	1,652
SBA Loan \| Significant Unobservable Inputs (Level 3) \| Fair Value
Servicing Asset at Amortized Cost [Line Items]
Servicing asset rights at fair value	8,050	$ 9,709
PPP Loans
Servicing Asset at Amortized Cost [Line Items]
Gain on sale of loans	$ 13,817

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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