CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Net revenues	$ 29,310	$ 24,105	$ 21,846
Operating Expenses
Personnel	4,990	4,240	3,785
Marketing	1,336	1,136	971
Network and processing	743	730	727
Professional fees	505	403	408
Depreciation and amortization	861	804	767
General and administrative	1,194	985	1,096
Litigation provision	868	3	11
Total operating expenses	10,497	8,301	7,765
Operating income	18,813	15,804	14,081
Non-operating Income (Expense)
Interest expense	(538)	(513)	(516)
Investment income (expense) and other	(139)	772	225
Total non-operating income (expense)	(677)	259	(291)
Income before income taxes	18,136	16,063	13,790
Income tax provision	3,179	3,752	2,924
Net income	$ 14,957	$ 12,311	$ 10,866
Class A common stock
Earnings Per Share [Abstract]
Basic earnings per share (in dollars per share)	$ 7.01	$ 5.63	$ 4.90
Basic weighted-average shares outstanding (in shares)	1,651	1,691	1,697
Diluted earnings per share (in dollars per share)	$ 7.00	$ 5.63	$ 4.89
Diluted weighted-average shares outstanding (in shares)	2,136	2,188	2,223
Class B common stock
Earnings Per Share [Abstract]
Basic earnings per share (in dollars per share)	$ 11.33	$ 9.14	$ 7.94
Basic weighted-average shares outstanding (in shares)	245	245	245
Diluted earnings per share (in dollars per share)	$ 11.31	$ 9.13	$ 7.93
Diluted weighted-average shares outstanding (in shares)	245	245	245
Class C common stock
Earnings Per Share [Abstract]
Basic earnings per share (in dollars per share)	$ 28.03	$ 22.53	$ 19.58
Basic weighted-average shares outstanding (in shares)	10	10	11
Diluted earnings per share (in dollars per share)	$ 28.00	$ 22.51	$ 19.56
Diluted weighted-average shares outstanding (in shares)	10	10	11