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Portfolio Loans Receivable and Allowance for Credit Losses - Classification of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 3,118,682		$ 2,965,071
Percent	100.00%		100.00%
Deferred origination fees, net	$ (4,418)		$ (5,614)
Allowance for credit losses	(55,493)	$ (54,431)	(54,660)	$ (53,045)	$ (47,447)	$ (48,652)
Total portfolio loans held for investment, net	3,058,771		2,904,797
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 774,297		$ 698,289
Percent	25.00%		23.00%
Allowance for credit losses	$ (19,608)	(18,474)	$ (19,818)	(20,017)	(16,249)	(16,377)
Real estate: \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 784,220		$ 765,808
Percent	25.00%		26.00%
Allowance for credit losses	$ (7,259)	(7,727)	$ (7,444)	(7,028)	(6,772)	(6,945)
Real estate: \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 1,024,754		$ 997,081
Percent	33.00%		34.00%
Allowance for credit losses	$ (13,879)	(14,387)	$ (14,917)	(14,865)	(14,262)	(16,041)
Real estate: \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 380,688		$ 359,566
Percent	12.00%		12.00%
Allowance for credit losses	$ (5,431)	(4,930)	$ (4,250)	(3,731)	(3,410)	(2,973)
Credit card \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 149,184		$ 142,397
Percent	5.00%		5.00%
Allowance for credit losses	$ (9,293)	(8,904)	$ (8,226)	(7,399)	(6,749)	(6,301)
Other consumer \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount	$ 5,539		$ 1,930
Percent	0.00%		0.00%
Allowance for credit losses	$ (23)	$ (9)	$ (5)	$ (5)	$ (5)	$ (15)