Portfolio Loans Receivable and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 54,431	$ 47,447	$ 54,660	$ 48,652	$ 48,652
Measurement Period Adjustment for Acquired PCD Loans		3,424		3,424
Provision (Release of Provision) for Credit Losses	4,903	4,650	11,502	10,977
Charge-Offs	(3,843)	(2,492)	(11,422)	(10,081)	(14,612)
Recoveries	2	16	753	73
Balance at end of period	55,493	53,045	55,493	53,045	54,660
Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-Offs			(180)		0
Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-Offs			0		(1,892)
Construction
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-Offs			(383)		(264)
Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	18,474	16,249	19,818	16,377	16,377
Measurement Period Adjustment for Acquired PCD Loans		3,424		3,424
Provision (Release of Provision) for Credit Losses	1,605	680	684	1,764
Charge-Offs	(471)	(336)	(1,639)	(1,597)	(3,420)
Recoveries	0	0	745	49
Balance at end of period	19,608	20,017	19,608	20,017	19,818
Real estate: \| Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	7,727	6,772	7,444	6,945	6,945
Measurement Period Adjustment for Acquired PCD Loans		0		0
Provision (Release of Provision) for Credit Losses	(296)	249	(7)	76
Charge-Offs	(174)	0	(180)	(1)
Recoveries	2	7	2	8
Balance at end of period	7,259	7,028	7,259	7,028	7,444
Real estate: \| Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	14,387	14,262	14,917	16,041	16,041
Measurement Period Adjustment for Acquired PCD Loans		0		0
Provision (Release of Provision) for Credit Losses	(508)	603	(1,038)	519
Charge-Offs	0	0	0	(1,695)
Recoveries	0	0	0	0
Balance at end of period	13,879	14,865	13,879	14,865	14,917
Real estate: \| Construction
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	4,930	3,410	4,250	2,973	2,973
Measurement Period Adjustment for Acquired PCD Loans		0		0
Provision (Release of Provision) for Credit Losses	501	321	1,564	1,022
Charge-Offs	0	0	(383)	(264)
Recoveries	0	0	0	0
Balance at end of period	5,431	3,731	5,431	3,731	4,250
Credit card \| Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	8,904	6,749	8,226	6,301	6,301
Measurement Period Adjustment for Acquired PCD Loans		0		0
Provision (Release of Provision) for Credit Losses	3,587	2,797	10,281	7,606
Charge-Offs	(3,198)	(2,156)	(9,220)	(6,524)	(9,036)
Recoveries	0	9	6	16
Balance at end of period	9,293	7,399	9,293	7,399	8,226
Other consumer \| Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	9	5	5	15	15
Measurement Period Adjustment for Acquired PCD Loans		0		0
Provision (Release of Provision) for Credit Losses	14	0	18	(10)
Charge-Offs	0	0	0	0
Recoveries	0	0	0	0
Balance at end of period	$ 23	$ 5	$ 23	$ 5	$ 5

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
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-Publisher FASB
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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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