CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net income	$ 3,126	$ 3,272
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Client incentives	1,858	1,748
Share-based compensation	122	116
Depreciation and amortization of property, equipment, technology and intangible assets	197	182
Deferred income taxes	5	(47)
VE territory covered losses incurred	(10)	(4)
Other	25	(50)
Change in operating assets and liabilities:
Settlement receivable	(244)	(183)
Accounts receivable	(108)	(107)
Client incentives	(1,485)	(1,943)
Other assets	235	123
Accounts payable	(39)	(12)
Settlement payable	194	218
Accrued and other liabilities	(357)	136
Accrued litigation	(6)	426
Net cash provided by (used in) operating activities	3,513	3,875
Investing Activities
Purchases of property, equipment and technology	(160)	(191)
Investment securities:
Purchases	(1,315)	(400)
Proceeds from maturities and sales	2,163	1,202
Acquisitions, net of cash acquired	(75)	(77)
Purchases of / contributions to other investments	(18)	(9)
Other investing activities	44	37
Net cash provided by (used in) investing activities	639	562
Financing Activities
Repurchase of class A common stock	(1,796)	(2,370)
Repayments of debt	(3,000)	0
Dividends paid	(703)	(671)
Cash proceeds from issuance of class A common stock under employee equity plans	61	55
Restricted stock and performance-based shares settled in cash for taxes	(134)	(147)
Net cash provided by (used in) financing activities	(5,572)	(3,133)
Effect of exchange rate changes on cash, cash equivalents, restricted cash and restricted cash equivalents	304	127
Increase (decrease) in cash, cash equivalents, restricted cash and restricted cash equivalents	(1,116)	1,431
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period	19,171	10,832
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	18,055	12,263
Supplemental Disclosure
Cash paid for income taxes, net	252	345
Interest payments on debt	281	234
Accruals related to purchases of property, equipment and technology	$ 13	$ 66