Loans and Leases Held for Investment at Amortized Cost, Net of Allowance for Loan and Lease Losses - Gross Charge-Offs by Origination Year (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)
Term Loans and Leases by Origination Year
Year 1	$ 23,542
Year 2	159,735
Year 3	96,197
Year 4	82
Year 5	318
Prior	1,233
Total	281,107
Consumer Portfolio Segment
Term Loans and Leases by Origination Year
Year 1	23,542
Year 2	159,735
Year 3	94,828
Year 4	0
Year 5	0
Prior	0
Total	278,105
Consumer Portfolio Segment \| Unsecured personal
Term Loans and Leases by Origination Year
Year 1	23,340
Year 2	157,502
Year 3	94,147
Year 4	0
Year 5	0
Prior	0
Total	274,989
Consumer Portfolio Segment \| Residential mortgages
Term Loans and Leases by Origination Year
Year 1	0
Year 2	0
Year 3	0
Year 4	0
Year 5	0
Prior	0
Total	0
Consumer Portfolio Segment \| Secured consumer
Term Loans and Leases by Origination Year
Year 1	202
Year 2	2,233
Year 3	681
Year 4	0
Year 5	0
Prior	0
Total	3,116
Commercial Portfolio Segment
Term Loans and Leases by Origination Year
Year 1	0
Year 2	0
Year 3	1,369
Year 4	82
Year 5	318
Prior	1,233
Total	3,002
Commercial Portfolio Segment \| Equipment finance
Term Loans and Leases by Origination Year
Year 1	0
Year 2	0
Year 3	0
Year 4	0
Year 5	0
Prior	0
Total	0
Commercial Portfolio Segment \| Commercial real estate
Term Loans and Leases by Origination Year
Year 1	0
Year 2	0
Year 3	0
Year 4	0
Year 5	0
Prior	0
Total	0
Commercial Portfolio Segment \| Commercial and industrial
Term Loans and Leases by Origination Year
Year 1	0
Year 2	0
Year 3	1,369
Year 4	82
Year 5	318
Prior	1,233
Total	$ 3,002

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

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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
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