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Loans - Nonaccrual Loans and Loans Past Due 90 Days or More (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual, interest income	$ 100	$ 100	$ 200	$ 100
Commercial Portfolio Segment \| Commercial and industrial \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	0		0		$ 0
Nonaccrual Loans with No Allowance for Credit Losses	0		0		0
Collateral dependent loans	16		16		0
Commercial Portfolio Segment \| Public finance \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	1,665		1,665		0
Nonaccrual Loans with No Allowance for Credit Losses	0		0		0
Collateral dependent loans	0		0		0
Commercial Portfolio Segment \| Small business lending \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	11,582		11,582		11,429
Nonaccrual Loans with No Allowance for Credit Losses	10,658		10,658		4,778
Collateral dependent loans	2,370		2,370		1,320
Commercial Portfolio Segment \| Franchise finance \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	23,857		23,857		10,382
Nonaccrual Loans with No Allowance for Credit Losses	1,781		1,781		0
Collateral dependent loans	0		0		0
Consumer Portfolio \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	41,155		41,155		25,955
Nonaccrual Loans with No Allowance for Credit Losses	16,490		16,490		8,922
Collateral dependent loans	2,386		2,386		2,466
Consumer Portfolio \| Residential mortgage \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	3,927		3,927		4,083
Nonaccrual Loans with No Allowance for Credit Losses	3,927		3,927		4,083
Collateral dependent loans	0		0		1,142
Consumer Portfolio \| Other consumer loans \| Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Nonaccrual Loans	124		124		61
Nonaccrual Loans with No Allowance for Credit Losses	124		124		61
Collateral dependent loans	$ 0		$ 0		$ 4