Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Jun. 30, 2024
Operating Activities:
Net income	$ 644	$ 463
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax	18	8
Amortization of other intangible assets	54	60	$ 230
Other non-cash adjustments for depreciation, amortization and accretion, net	34	121
Provision for credit losses	12	27
Change in trading account assets, net	25	13
Change in accrued interest and fees receivable, net	(247)	(206)
Change in collateral deposits, net	(1,697)	(575)
Change in unrealized losses (gains) on foreign exchange derivatives, net	4,613	(4,251)
Change in other assets, net	(1,761)	1,176
Change in accrued expenses and other liabilities, net	545	2,219
Other, net	156	101
Net cash provided by (used in) operating activities	2,396	(844)
Investing Activities:
Net increase in interest-bearing deposits with banks	(6,507)	(37,821)
Net increase in securities purchased under resale agreements	(1,291)	(797)
Proceeds from sales of available-for-sale securities	2,047	943
Proceeds from maturities of available-for-sale securities	8,832	4,484
Purchases of available-for-sale securities	(18,449)	(9,857)
Proceeds from maturities of held-to-maturity securities	2,333	4,144
Purchases of held-to-maturity securities	0	(3)
Sale of loans	85	53
Net increase in loans	(1,281)	(2,248)
Business acquisitions, net of cash acquired	0	(12)
Purchases of equity investments and other long-term assets	(47)	(31)
Purchases of premises and equipment, net	(226)	(230)
Other, net	(103)	23
Net cash (used in) investing activities	(14,607)	(41,352)
Financing Activities:
Net increase (decrease) in time deposits	2,663	(2,127)
Net increase in all other deposits	7,469	33,044
Net (decrease) increase in securities sold under repurchase agreements	(157)	1,709
Net increase in other short-term borrowings	2,010	7,881
Proceeds from issuance of long-term debt, net of issuance costs	2,737	996
Payments for long-term debt and obligations under finance leases	(1,312)	(12)
Payments for redemption of preferred stock	0	(1,000)
Proceeds from issuance of preferred stock, net of issuance costs	743	1,481
Repurchases of common stock	(100)	(119)
Repurchases of common stock for employee tax withholding	(57)	(42)
Payments for cash dividends	(266)	(243)
Other, net	(6)	(6)
Net cash provided by financing activities	13,724	41,562
Net increase (decrease) in cash and due from banks	1,513	(634)
Cash and due from banks at beginning of period	3,145	4,047	$ 4,047
Cash and due from banks at end of period	4,658	3,413
Supplemental disclosure:
Interest paid	2,074	1,989
Income taxes paid, net	$ 186	$ 118