Business Segment Results of Operations (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 4,151	$ 4,147
Earnings	423	591
Interest expense	(35)	(43)
Operating Segments [Member] \| Automation Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	2,852	2,799
Earnings	310	407
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	1,303	1,338
Earnings	237	237
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Net sales	873	880
Earnings	151	146
Operating Segments [Member] \| Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Net sales	430	458
Earnings	86	91
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Stock compensation	(56)	7
Unallocated pension and postretirement costs	13	27
Interest expense	(35)	(43)
Corporate and other [Member]
Segment Reporting Information [Line Items]
Earnings	(46)	(44)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	$ (4)	$ 10

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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