Borrowed Funds (Remaining Maturity) (Details) $ in Millions	Mar. 31, 2024 USD ($)
Debt Disclosure [Abstract]
Less than 1 year	$ 27,205
1 to 2 years	15,243
2 to 3 years	6,927
3 to 4 years	4,572
4 to 5 years	2,386
Over 5 years	16,374
Total	$ 72,707

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