Segment Information - Financial Information Related to Company's Reportable Segments (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Information [Line Items]
Net sales	$ 6,614	$ 6,341	$ 18,574	$ 17,276
Segment EBITA	998	1,020	2,521	2,373
Corporate expenses	(96)	(70)	(226)	(207)
Amortization of intangible assets	(102)	(112)	(326)	(320)
Restructuring and impairment costs	(121)	(79)	(554)	(175)
Net mark-to-market adjustments	(126)	66	(158)	296
Net financing charges	(49)	(56)	(153)	(159)
Income from continuing operations before income taxes	504	769	1,104	1,808
Building Solutions North America
Segment Reporting Information [Line Items]
Net sales	2,426	2,212	6,805	6,338
Segment EBITA	260	326	745	847
Building Solutions EMEA/LA
Segment Reporting Information [Line Items]
Net sales	952	1,001	2,869	2,883
Segment EBITA	83	105	266	291
Building Solutions Asia Pacific
Segment Reporting Information [Line Items]
Net sales	665	703	1,963	1,901
Segment EBITA	85	84	227	234
Global Products
Segment Reporting Information [Line Items]
Net sales	2,571	2,425	6,937	6,154
Segment EBITA	$ 570	$ 505	$ 1,283	$ 1,001

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