Short-Term Borrowings (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Percentage of outstanding advance for unencumbered collateral	100.00%
Federal Reserve Bank Advances
Short-term Debt [Line Items]
Amount available for FHLB advances	$ 9,800	$ 4,000
Federal Funds Purchased and Securities Sold under Agreements to Repurchase
Short-term Debt [Line Items]
Maturity period	30 days
Federal Home Loan Bank advances
Short-term Debt [Line Items]
Amount available for FHLB advances	$ 15,000	$ 9,400

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480876/942-470-45-1

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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- Definition

Percentage of outstanding advance for unencumbered collateral

+ References

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