Deposits and Borrowings - Deposits and Short-term Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Deposits:
Non-interest-bearing deposits	$ 27,936	$ 27,385
Interest-bearing deposits	461,117	448,386
Total deposits	489,053	475,771	$ 367,464
Short-term borrowings:
Total short-term borrowings	1,626	1,087
Federal funds purchased and securities loaned or sold under agreements to repurchase
Short-term borrowings:
Total short-term borrowings	626	587
Short-term FHLB advances
Short-term borrowings:
Total short-term borrowings	$ 1,000	$ 500

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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