Short-Term Borrowings (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Short-term Debt [Line Items]
Percentage of outstanding advance for unencumbered collateral	100.00%
Amount available for FHLB advances	$ 9,400
Amount available for Federal Reserve borrowings	10,417	$ 903
Federal Reserve Bank Advances
Short-term Debt [Line Items]
Amount available for Federal Reserve borrowings	$ 4,000
Federal Funds Purchased and Securities Sold under Agreements to Repurchase
Short-term Debt [Line Items]
Maturity period	30 days

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.

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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Percentage of outstanding advance for unencumbered collateral

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