Loans Receivable and Allowance for Credit Losses - Allowance for Credit Losses Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2024 USD ($) qtr	Dec. 31, 2023 USD ($)
Financing Receivable Allowance for Credit Losses
Life time loss rate, period span \| qtr	8
Allowance for credit losses	$ 736	$ 706
Increase in allowance for credit losses	30
Commercial lending
Financing Receivable Allowance for Credit Losses
Collateral dependent loan	45	30
Consumer lending
Financing Receivable Allowance for Credit Losses
Collateral dependent loan	$ 18	$ 12

Financing Receivable And Off Balance Sheet Credit Loss Allowance

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- Definition

Financing Receivable And Off Balance Sheet Credit Loss Allowance, Period Increase (Decrease)

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Collateral Dependent

+ References

No definition available.

+ Details

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- Definition

Reasonable and Supportable Forecast Period, Life Time Loss Rate, Period

+ References

No definition available.

+ Details

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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
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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