Sales of Receivables and Servicing Rights - Servicing Rights and Residual Interests Economic Assumptions (Details)	3 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Fixed-rate
Schedule of Servicing Assets at Amortized Value
Weighted- Average Life (in years)	6 years 9 months 18 days	7 years 7 months 6 days
Prepayment Speed (annual) (as a percent)	12.00%	8.40%
OAS (bps)	609	795
Adjustable-rate
Schedule of Servicing Assets at Amortized Value
Weighted- Average Life (in years)	0 years	2 years 10 months 24 days
Prepayment Speed (annual) (as a percent)	0.00%	27.30%
OAS (bps)	0	789

Option adjusted spread basis points.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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- Definition

Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

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