Borrowed Funds (Remaining Maturity) (Details) $ in Millions	Sep. 30, 2023 USD ($)
Debt Disclosure [Abstract]
Less than 1 year	$ 14,193
1 to 2 years	21,763
2 to 3 years	12,138
3 to 4 years	1,945
4 to 5 years	2,931
Over 5 years	13,197
Total	$ 66,167

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