Consolidated Statement of Equity Statement - USD ($) $ in Millions	Total	AspenTech	Common stock	Additional paid-in-capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Noncontrolling interests in subsidiaries
Beginning balance at Sep. 30, 2020				$ 470	$ 24,955	$ (1,577)	$ (15,920)	$ 42
Statement [Roll Forward]
Stock plans				48
Adjustments to Additional Paid in Capital, Other				0
Net earnings common stockholders	$ 1,633				1,633
Dividends paid (per share: $0.515, $0.505, $1.545 and $1.515, respectively)					(909)			(14)
AspenTech acquisition								0
Adoption of accounting standard					(1)
Foreign currency translation	163					163
Amortization of deferred actuarial losses into earnings, net of tax of $(5) and $(8), respectively	(81)					81
Cash flow hedges	26					26
Purchases							(275)
Issued under stock plans							120
Net earnings								20
Stock compensation								0
Other comprehensive income	270							0
Ending balance at Jun. 30, 2021	9,339		$ 477	518	25,678	(1,307)	(16,075)	48
Beginning balance at Mar. 31, 2021				511	25,354	(1,322)	(15,890)	50
Statement [Roll Forward]
Stock plans				7
Adjustments to Additional Paid in Capital, Other				0
Net earnings common stockholders	627				627
Dividends paid (per share: $0.515, $0.505, $1.545 and $1.515, respectively)					(303)			(9)
AspenTech acquisition								0
Adoption of accounting standard					0
Foreign currency translation	(5)					(6)
Amortization of deferred actuarial losses into earnings, net of tax of $(5) and $(8), respectively	(27)					27
Cash flow hedges	(6)					(6)
Purchases							(193)
Issued under stock plans							8
Net earnings								6
Stock compensation								0
Other comprehensive income	16							1
Ending balance at Jun. 30, 2021	9,339		477	518	25,678	(1,307)	(16,075)	48
Statement [Roll Forward]
Common stockholders' equity	9,291
Common stockholders' equity	9,883
Beginning balance at Sep. 30, 2021	9,923			522	26,047	(872)	(16,291)	40
Statement [Roll Forward]
Stock plans				70
Adjustments to Additional Paid in Capital, Other				(550)
Net earnings common stockholders	2,491				2,491
Dividends paid (per share: $0.515, $0.505, $1.545 and $1.515, respectively)					(920)			(2)
AspenTech acquisition								5,890
Adoption of accounting standard					0
Foreign currency translation	(319)					(317)
Amortization of deferred actuarial losses into earnings, net of tax of $(5) and $(8), respectively	(54)					54
Cash flow hedges	(17)					(17)
Purchases							(430)
Issued under stock plans							51
Net earnings								31
Stock compensation		$ 15						15
Other comprehensive income	(282)							(2)
Ending balance at Jun. 30, 2022	16,287		477	42	27,618	(1,152)	(16,670)	5,972
Beginning balance at Mar. 31, 2022				579	27,003	(957)	(16,527)	39
Statement [Roll Forward]
Stock plans				13
Adjustments to Additional Paid in Capital, Other		550		(550)
Net earnings common stockholders	921				921
Dividends paid (per share: $0.515, $0.505, $1.545 and $1.515, respectively)					(306)			(2)
AspenTech acquisition								5,890
Adoption of accounting standard					0
Foreign currency translation	(187)					(186)
Amortization of deferred actuarial losses into earnings, net of tax of $(5) and $(8), respectively	(18)					18
Cash flow hedges	(27)					(27)
Purchases							(145)
Issued under stock plans							2
Net earnings								31
Stock compensation		$ 15						15
Other comprehensive income	(196)							(1)
Ending balance at Jun. 30, 2022	16,287		$ 477	$ 42	$ 27,618	$ (1,152)	$ (16,670)	$ 5,972
Statement [Roll Forward]
Common stockholders' equity	$ 10,315