CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Activities
Net income	$ 4,890	$ 4,179
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Client incentives	3,348	2,786
Share-based compensation	209	177
Depreciation and amortization	247	227
Deferred income taxes	59	(132)
VE territory covered losses incurred	(24)	(8)
(Gains) losses on equity investments, net	(4)	106
Other	11	(26)
Change in operating assets and liabilities:
Settlement receivable	(257)	(54)
Accounts receivable	(195)	(60)
Client incentives	(3,601)	(2,743)
Other assets	(204)	160
Accounts payable	(18)	(64)
Settlement payable	313	44
Accrued and other liabilities	(877)	(666)
Accrued litigation	(283)	245
Net cash provided by (used in) operating activities	3,614	4,171
Investing Activities
Purchases of property, equipment and technology	(267)	(249)
Investment securities:
Purchases	(2,743)	(1,995)
Proceeds from maturities and sales	1,137	1,310
Purchases of other investments	(11)	(20)
Settlement of derivative instruments	0	402
Other investing activities	(5)	42
Net cash provided by (used in) investing activities	(1,889)	(510)
Financing Activities
Repurchase of class A common stock	(3,580)	(3,115)
Repayments of debt	0	(2,250)
Dividends paid	(1,060)	(945)
Cash proceeds from issuance of class A common stock under equity plans	104	56
Restricted stock and performance-based shares settled in cash for taxes	(172)	(112)
Other financing activities	329	19
Net cash provided by (used in) financing activities	(4,379)	(6,347)
Effect of exchange rate changes on cash, cash equivalents, restricted cash and restricted cash equivalents	300	692
Increase (decrease) in cash, cash equivalents, restricted cash and restricted cash equivalents	(2,354)	(1,994)
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period	21,990	20,377
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	19,636	18,383
Supplemental Disclosure
Cash paid for income taxes, net	1,503	721
Interest payments on debt	213	244
Accruals related to purchases of property, equipment and technology	$ 26	$ 27