Fair Value Measures - Changes in Fair Value Included in Earnings - Fair Value Option (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Weighted-average life		6 years 11 months 15 days
Loans held-for-sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Change in fair value included in earnings	$ 29	$ 57

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 820
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

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Weighted average life of financial assets and financial liabilities, 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/2009/role/commonPracticeRef
-Topic 860
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