Business Segment Information Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 211	$ 202
Corporate and other [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	9	9
Operating Segments [Member] | Automation Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	139	129
Operating Segments [Member] | Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	63	64
Operating Segments [Member] | Climate Technologies [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	44	45
Operating Segments [Member] | Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 19	$ 19