Derivative Financial Instruments - Risk Participation Agreements and Total Return Swaps (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Risk Participation Agreements Sold
Credit Derivatives [Line Items]
Maximum potential amount of exposure	$ 543	$ 575
Total Return Swap
Credit Derivatives [Line Items]
Cash collateral held	$ 461	$ 453

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

+ Details

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Balance Type:	debit
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- Definition

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4K

+ Details

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Period Type:	instant

- 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

No definition available.

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- Details

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- Details

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