Deposits and Borrowings - Deposits and Short-term Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Deposits [Abstract]
Non-interest-bearing deposits	$ 31,186	$ 32,203
Interest-bearing deposits	318,641	300,789
Total deposits	349,827	332,992	$ 313,429
Short-term borrowings
Short-term borrowings	542	883
Time deposits, at or above FDIC insurance limit	14,000	6,100
Deposit Liability, Uninsured		2,000	$ 9,900
Federal funds purchased and securities loaned or sold under agreements to repurchase
Short-term borrowings
Short-term borrowings	$ 542	$ 883

Amount of uninsured deposit liability.

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-Name Regulation S-K (SK)
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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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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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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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