Business Combinations - Schedule of Unpaid Balance and Fair Value of the Acquired Loan Portfolio (Details) - USD ($) $ in Millions	Mar. 27, 2023	Jan. 03, 2022
SVB
Business Acquisition [Line Items]
UPB	$ 71,287
Loans and Leases, FV	68,468
SVB \| Non-PCD
Business Acquisition [Line Items]
UPB	68,719
Loans and Leases, FV	66,422
SVB \| PCD
Business Acquisition [Line Items]
UPB	2,568
Loans and Leases, FV	$ 2,046
CIT Group Inc.
Business Acquisition [Line Items]
UPB		$ 33,092
Loans and Leases, FV		32,714
CIT Group Inc. \| Non-PCD
Business Acquisition [Line Items]
UPB		29,542
Loans and Leases, FV		29,481
CIT Group Inc. \| PCD
Business Acquisition [Line Items]
UPB		3,550
Loans and Leases, FV		$ 3,233

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-19

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Amount at purchase price of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-19

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