Sales of Receivables and Servicing Rights - Servicing Rights and Residual Interests Economic Assumptions (Details) - bps	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Fixed Rate Residential Mortgage
Schedule of Servicing Assets at Amortized Value
Weighted- Average Life (in years)	5 years 10 months 24 days	5 years 9 months 18 days
Prepayment Speed Assumption, Rate (as a percent)	12.30%	12.40%
OAS Speed Assumption, OAS (bps)	610	777
Adjustable Rate Residential Mortgage
Schedule of Servicing Assets at Amortized Value
Weighted- Average Life (in years)	0 years	3 years
Prepayment Speed Assumption, Rate (as a percent)	0.00%	27.10%
OAS Speed Assumption, OAS (bps)	0	725

Option adjusted spread basis points.

No definition available.

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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

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

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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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