Net Interest Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Interest income:
Interest-bearing deposits with banks	$ 792	$ 929	$ 1,561	$ 1,927
Investment securities:
Investment securities available-for-sale	753	672	1,477	1,244
Investment securities held-to-maturity	234	277	475	571
Total investment securities	987	949	1,952	1,815
Securities purchased under resale agreements	179	166	344	333
Loans	574	563	1,130	1,109
Other interest-earning assets	523	391	990	703
Total interest income	3,055	2,998	5,977	5,887
Interest expense:
Interest-bearing deposits	1,693	1,637	3,259	3,277
Securities sold under repurchase agreements	35	43	86	82
Other short-term borrowings	114	167	250	268
Long-term debt	322	267	619	525
Other interest-bearing liabilities	162	149	320	284
Total interest expense	2,326	2,263	4,534	4,436
Net interest income	$ 729	$ 735	$ 1,443	$ 1,451

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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The aggregate interest expense incurred on short-term borrowings including commercial paper and Federal funds purchased and securities sold under agreements to repurchase.

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