Other Financial Information (Details) - USD ($) $ in Millions	Mar. 31, 2017	Sep. 30, 2016
Other Financial Information [Line Items]
Finished products	$ 434	$ 382
Raw materials and work in process	897	826
Total	1,331	1,208
Property, plant and equipment, at cost	7,405	7,327
Less: Accumulated depreciation	4,525	4,396
Total	2,880	2,931
Goodwill, net	3,891	3,909
Employee compensation	375	431
Customer advanced payments	471	433
Product warranty	97	106
Pension liabilities	762	844
Deferred income taxes	182	210
Postretirement liabilities, excluding current portion	190	193
Other	499	482
Total	1,633	1,729
Automation Solutions [Member]
Other Financial Information [Line Items]
Goodwill, net	3,146	3,160
Commercial & Residential Solutions [Member]
Other Financial Information [Line Items]
Goodwill, net	745	749
Tools & Home Products [Member]
Other Financial Information [Line Items]
Goodwill, net	195	196
Climate Technologies [Member]
Other Financial Information [Line Items]
Goodwill, net	$ 550	$ 553