Portfolio Loans Receivable and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 28,610	$ 27,189	$ 27,189
Provision (Release of Provision) for Credit Losses	2,727	1,660
Charge-Offs	(2,091)	(2,645)	(8,787)
Recoveries	104	12
Ending balance	29,350	26,216	28,610
Residential
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-Offs	(225)		(670)
Residential \| Real estate:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	5,518	4,283	4,283
Provision (Release of Provision) for Credit Losses	633	1,125
Charge-Offs	(225)	0
Recoveries	0	0
Ending balance	5,926	5,408	5,518
Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-Offs			(943)
Commercial \| Real estate:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,316	12,039	12,039
Provision (Release of Provision) for Credit Losses	807	(2,165)
Charge-Offs	0	(943)
Recoveries	0	0
Ending balance	11,123	8,931	10,316
Construction \| Real estate:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,271	1,809	1,809
Provision (Release of Provision) for Credit Losses	28	(56)
Charge-Offs	0	0
Recoveries	0	0
Ending balance	2,299	1,753	2,271
Commercial and Industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,406	4,008	4,008
Provision (Release of Provision) for Credit Losses	(306)	940
Charge-Offs	(98)	0	(98)
Recoveries	0	10
Ending balance	4,002	4,958	4,406
Consumer \| Credit card
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,087	5,033	5,033
Provision (Release of Provision) for Credit Losses	1,567	1,818
Charge-Offs	(1,768)	(1,702)	(7,076)
Recoveries	104	2
Ending balance	5,990	5,151	6,087
Consumer \| Other consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	12	17	17
Provision (Release of Provision) for Credit Losses	(2)	(2)
Charge-Offs	0	0
Recoveries	0	0
Ending balance	$ 10	$ 15	$ 12

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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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
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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+ References

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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