Business Combinations - Schedule of Unpaid Balance and Fair Value of the Acquired Loan Portfolio (Details) - SVB $ in Millions	Mar. 27, 2023 USD ($)
Business Acquisition [Line Items]
UPB	$ 71,287
Loans and Leases, FV	68,460
Non-PCD
Business Acquisition [Line Items]
UPB	68,729
Loans and Leases, FV	66,424
PCD
Business Acquisition [Line Items]
UPB	2,558
Loans and Leases, FV	$ 2,036

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
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (d)
-Publisher FASB
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Amount at purchase price of financing receivable purchased with credit deterioration.

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

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