Segment Information - Financial Information Related to Company's Reportable Segments (Detail) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales	$ 5,862	$ 5,341
Segment EBITA	723	642
Corporate expenses	(70)	(67)
Amortization of intangible assets	(118)	(104)
Restructuring and impairment costs	(49)	0
Net mark-to-market adjustments	57	21
Net financing charges	(53)	(59)
Income from continuing operations before income taxes	490	433
Building Solutions North America
Segment Reporting Information [Line Items]
Net sales	2,152	2,034
Segment EBITA	250	255
Building Solutions EMEA/LA
Segment Reporting Information [Line Items]
Net sales	959	948
Segment EBITA	104	98
Building Solutions Asia Pacific
Segment Reporting Information [Line Items]
Net sales	675	604
Segment EBITA	68	77
Global Products
Segment Reporting Information [Line Items]
Net sales	2,076	1,755
Segment EBITA	$ 301	$ 212

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