CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (UNAUDITED) - USD ($) shares in Millions, $ in Millions		Total	Preferred Stock		Common Stock and Additional Paid-in Capital	Right to Recover for Covered Losses	Accumulated Income	Accumulated Other Comprehensive Income (Loss), Net
Beginning balance (in shares) at Sep. 30, 2021			5
Beginning balance at Sep. 30, 2021		$ 37,589	$ 3,080	[1]	$ 18,855	$ (133)	$ 15,351	$ 436
Beginning balance (in shares) at Sep. 30, 2021					1,932
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		3,959					3,959
Other Comprehensive Income (Loss), Net of Tax		(508)						(508)
VE territory covered losses incurred		(7)				(7)
Recovery through conversion rate adjustment		0	$ (29)			29
Conversion to class A common stock upon sales into public market (in shares)			0	[2]	1
Conversion to class A common stock upon sales into public market		0	$ (56)		$ 56
Share-based compensation, net of forfeitures		128			$ 128
Stock issued under equity plans (in shares)					2
Stock issued under equity plans		59			$ 59
Restricted stock and performance-based shares settled in cash for taxes (in shares)	[2]				0
Restricted stock and performance-based shares settled in cash for taxes		(113)			$ (113)
Cash dividends declared and paid, at a quarterly amount per class A common stock		(809)					(809)
Repurchase of class A common stock (in shares)					(19)
Repurchase of class A common stock		(4,104)			$ (209)		(3,895)
Ending balance (in shares) at Dec. 31, 2021			5
Ending balance at Dec. 31, 2021		36,194	$ 2,995	[1]	$ 18,776	(111)	14,606	(72)
Ending balance (in shares) at Dec. 31, 2021					1,916
Beginning balance (in shares) at Sep. 30, 2022			5
Beginning balance at Sep. 30, 2022		35,581	$ 2,324	[3]	$ 19,545	(35)	16,116	(2,369)
Beginning balance (in shares) at Sep. 30, 2022					1,890
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		4,179					4,179
Other Comprehensive Income (Loss), Net of Tax		1,110						1,110
VE territory covered losses incurred		(8)				(8)
Recovery through conversion rate adjustment		1	$ (14)			15
Conversion to class A common stock upon sales into public market (in shares)			0	[4]	5
Conversion to class A common stock upon sales into public market		0	$ (329)		$ 329
Share-based compensation, net of forfeitures		177			$ 177
Stock issued under equity plans (in shares)					2
Stock issued under equity plans		56			$ 56
Restricted stock and performance-based shares settled in cash for taxes (in shares)	[4]				0
Restricted stock and performance-based shares settled in cash for taxes		(112)			$ (112)
Cash dividends declared and paid, at a quarterly amount per class A common stock		(945)					(945)
Repurchase of class A common stock (in shares)					(16)
Repurchase of class A common stock		(3,115)			$ (168)		(2,947)
Ending balance (in shares) at Dec. 31, 2022			5
Ending balance at Dec. 31, 2022		$ 36,924	$ 1,981	[3]	$ 19,827	$ (28)	$ 16,403	$ (1,259)
Ending balance (in shares) at Dec. 31, 2022					1,881

[1] As of December 31, 2021 and September 30, 2021, the book value of series A preferred stock was $430 million and $486 million, respectively. Refer to Note 4—U.S. and Europe Retrospective Responsibility Plans for the book value of series B and series C preferred stock.

[2] Increase or decrease is less than one million shares.

[3] As of December 31, 2022 and September 30, 2022, the book value of series A preferred stock was $723 million and $1.0 billion, respectively. Refer to Note 4—U.S. and Europe Retrospective Responsibility Plans for the book value of series B and series C preferred stock.

[4] Increase or decrease is less than one million shares.