CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net income	$ 769	$ 667
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Depreciation and amortization	69	64
Deferred income taxes, net	12	27
Premium and discount amortization on available-for-sale securities and net (gain)/loss on other investments	24	14
Provisions/(benefits) for credit losses and legal and regulatory proceedings	16	(14)
Share-based compensation expense	109	74
Unrealized (gain)/loss on company-owned life insurance policies, net of expenses	19	(117)
Other	10	31
Net change in:
Assets segregated for regulatory purposes excluding cash and cash equivalents	(8,294)	(5,250)
Collateralized agreements, net of collateralized financings	59	1
Loans provided to financial advisors, net of repayments	(76)	(11)
Brokerage client receivables and other receivables, net	(299)	(123)
Trading instruments, net	160	(90)
Derivative instruments, net	166	91
Other assets	(39)	(23)
Brokerage client payables and other payables	6,556	5,491
Accrued compensation, commissions and benefits	(278)	(29)
Purchases and originations of loans held for sale, net of proceeds from sales of securitizations and loans held for sale	(153)	(67)
Net cash provided by/(used in) operating activities	(1,170)	736
Cash flows from investing activities:
Increase in bank loans, net	(2,850)	(1,522)
Proceeds from sales of loans held for investment	134	90
Purchases of available-for-sale securities	(1,992)	(2,273)
Available-for-sale securities maturations, repayments and redemptions	952	1,067
Proceeds from sales of available-for-sale securities	0	519
Cash and cash equivalents acquired in business acquisitions, including those segregated for regulatory purposes, net of cash paid for acquisitions	1,671	(245)
Additions to property and equipment	(42)	(62)
Investment in note receivable	(125)	0
Purchases of other investments, net	(80)	(4)
Other investing activities, net	(71)	(7)
Net cash used in investing activities	(2,403)	(2,437)
Cash flows from financing activities:
Increase in bank deposits	2,190	2,453
Repurchases of common stock and share-based awards withheld for payment of withholding tax requirements	(59)	(99)
Dividends on common stock	(131)	(109)
Exercise of stock options and employee stock purchases	32	32
Other financing, net	(5)	0
Net cash provided by financing activities	2,025	2,249
Currency adjustment:
Effect of exchange rate changes on cash	(49)	93
Net increase/(decrease) in cash and cash equivalents, including those segregated for regulatory purposes and restricted cash	(1,597)	641
Cash and cash equivalents, including those segregated for regulatory purposes and restricted cash at beginning of year	16,449	9,634
Cash and cash equivalents, including those segregated for regulatory purposes and restricted cash at end of period	14,852	10,275
Cash and cash equivalents, including those segregated for regulatory purposes and restricted cash
Cash and cash equivalents	5,715	5,851
Cash and cash equivalents segregated for regulatory purposes and restricted cash	9,137	4,424
Total cash and cash equivalents, including those segregated for regulatory purposes and restricted cash at end of period	14,852	10,275
Supplemental disclosures of cash flow information:
Cash paid for interest	76	76
Cash paid for income taxes, net	293	248
Cash outflows for lease liabilities	52	56
Non-cash right-of-use assets recorded for new and modified leases	26	81
FHLB advances
Cash flows from financing activities:
Proceeds from Federal Home Loan Bank advances	850	0
Repayments of Federal Home Loan Bank advances and other borrowed funds	$ (852)	$ (28)