Deposits and Borrowings - Maturity Profile of Borrowings (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Time Deposits, Fiscal Year Maturity:
2022	$ 11,518
2023	3,026
2024	2,427
2025	444
2026	468
Thereafter	40
Total	17,923
Debt Fiscal Year Maturity:
Short-term borrowings	820	$ 668
Total, Fiscal Year Maturity:
2022	20,357
2023	9,565
2024	13,493
2025	4,520
2026	4,395
Thereafter	8,679
Total	61,009
Securitized debt obligations
Debt Fiscal Year Maturity:
2022	5,537
2023	527
2024	4,862
2025	731
2026	1,882
Thereafter	1,455
Long-term Debt	14,994	12,414
Senior and subordinated notes
Debt Fiscal Year Maturity:
2022	2,462
2023	5,993
2024	6,200
2025	3,343
2026	2,043
Thereafter	7,178
Long-term Debt	27,219	27,382
Other borrowings
Debt Fiscal Year Maturity:
2022	20
2023	19
2024	4
2025	2
2026	2
Thereafter	6
Long-term Debt	53
Federal funds purchased and securities loaned or sold under agreements to repurchase
Debt Fiscal Year Maturity:
Short-term debt, maturities, next 12 months	820
Short-term borrowings	$ 820	$ 668

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