Business Segments Information (Financial Information By Geographic Area) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Net sales	$ 4,971	$ 4,684	$ 4,570	$ 4,147	$ 4,888	$ 4,456	$ 4,248	$ 3,816	$ 18,372	$ 17,408	$ 15,264
United States
Segment Reporting Information [Line Items]
Net sales									8,390	7,939	7,273
Property, Plant and Equipment	2,128				2,027				2,128	2,027	1,840
China
Segment Reporting Information [Line Items]
Net sales									1,962	1,955	1,540
Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Net sales									18,371	17,423	15,275
Property, Plant and Equipment	3,642				3,562				3,642	3,562	3,321
Reportable Geographical Components [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales									10,103	9,484	8,632
Property, Plant and Equipment	2,339				2,234				2,339	2,234	2,055
Reportable Geographical Components [Member] | Asia, Middle East & Africa
Segment Reporting Information [Line Items]
Net sales									5,083	5,041	4,209
Property, Plant and Equipment	671				652				671	652	640
Reportable Geographical Components [Member] | Europe [Member]
Segment Reporting Information [Line Items]
Net sales									3,185	2,898	2,434
Property, Plant and Equipment	$ 632				$ 676				632	676	626
Automation Solutions [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Net sales									12,202	11,441	9,418
Automation Solutions [Member] | Reportable Geographical Components [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales									5,850	5,517	4,581
Automation Solutions [Member] | Reportable Geographical Components [Member] | Asia, Middle East & Africa
Segment Reporting Information [Line Items]
Net sales									3,891	3,657	2,936
Automation Solutions [Member] | Reportable Geographical Components [Member] | Europe [Member]
Segment Reporting Information [Line Items]
Net sales									2,461	2,267	1,901
Commercial & Residential Solutions [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Net sales									6,169	5,982	5,857
Commercial & Residential Solutions [Member] | Reportable Geographical Components [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales									4,253	3,967	4,051
Commercial & Residential Solutions [Member] | Reportable Geographical Components [Member] | Asia, Middle East & Africa
Segment Reporting Information [Line Items]
Net sales									1,192	1,384	1,273
Commercial & Residential Solutions [Member] | Reportable Geographical Components [Member] | Europe [Member]
Segment Reporting Information [Line Items]
Net sales									$ 724	$ 631	$ 533