Securitizations and Variable Interest Entities (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Sales of financial assets	$ 0	$ 0
Off-balance sheet variable interest entities \| Consumer Automotive Industry Sector
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Net credit losses recognized	$ 0	$ 0

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.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net credit losses are charge-offs and are based on total loans outstanding during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (e)(5)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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