Other Financial Information (Details) - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016
Other Financial Information [Line Items]
Finished products	$ 678	$ 382
Raw materials and work in process	1,213	826
Total	1,891	1,208
Property, plant and equipment, at cost	7,921	7,327
Less: Accumulated depreciation	4,617	4,396
Total	3,304	2,931
Goodwill by business segment	5,296	3,909
Employee compensation	506	431
Customer advanced payments	531	433
Product warranty	111	106
Pension and postretirement liabilities	941	1,037
Deferred income taxes	426	210
Other	846	482
Total	2,213	1,729
Automation Solutions [Member]
Other Financial Information [Line Items]
Goodwill by business segment	4,545	3,160
Commercial & Residential Solutions [Member]
Other Financial Information [Line Items]
Goodwill by business segment	751	749
Tools & Home Products [Member]
Other Financial Information [Line Items]
Goodwill by business segment	196	196
Climate Technologies [Member]
Other Financial Information [Line Items]
Goodwill by business segment	555	$ 553
Asbestos Issue [Member]
Other Financial Information [Line Items]
Asbestos liabilities, gross	245
Insurance receivables	$ 100

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