Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 237	$ 209	$ 720	$ 631
Corporate, non-segment [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	17	8	53	26
Operating Segments [Member] | Automation Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	152	137	464	414
Operating Segments [Member] | Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	68	64	203	191
Operating Segments [Member] | Climate Technologies [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	48	44	144	133
Operating Segments [Member] | Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 20	$ 20	$ 59	$ 58