Deposits and Borrowings - Maturity Profile of Borrowings (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Time Deposits, Fiscal Year Maturity:
2024	$ 60,838
2025	10,971
2026	3,232
2027	5,932
2028	1,747
Thereafter	294
Total	83,014
Debt Fiscal Year Maturity:
Short-term borrowings	538	$ 883
Total, Fiscal Year Maturity:
2024	68,496
2025	21,976
2026	11,251
2027	11,754
2028	6,823
Thereafter	12,570
Total	132,870
Securitized debt obligations
Debt Fiscal Year Maturity:
2024	4,085
2025	6,519
2026	3,607
2027	1,621
2028	2,211
Thereafter	0
Total	18,043	16,973
Senior and subordinated notes
Debt Fiscal Year Maturity:
2024	3,026
2025	4,480
2026	4,407
2027	4,198
2028	2,862
Thereafter	12,275
Total	31,248	30,826
Other borrowings
Debt Fiscal Year Maturity:
2024	9
2025	6
2026	5
2027	3
2028	3
Thereafter	1
Total	27
Federal funds purchased and securities loaned or sold under agreements to repurchase
Debt Fiscal Year Maturity:
Short-term debt, maturities, next 12 months	538
Short-term borrowings	$ 538	$ 883

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