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Business Segments Information (Results Of Operations By Business Segments ) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Net sales	$ 4,558	$ 3,914	$ 4,162	$ 4,151	$ 4,971	$ 4,684	$ 4,570	$ 4,147	$ 16,785	$ 18,372	$ 17,408
Stock compensation									110	120	216
Earnings before income taxes									2,335	2,859	2,667
Total Assets	22,882				20,497				22,882	20,497	20,390
Interest Income (Expense), Nonoperating, Net									(156)	(174)	(159)
Automation Solutions [Member] \| Measurement & Analytical Instrumentation [Member]
Segment Reporting Information [Line Items]
Net sales									3,237	3,807	3,604
Automation Solutions [Member] \| Valves, Actuators & Regulators [Member]
Segment Reporting Information [Line Items]
Net sales									3,589	3,794	3,749
Automation Solutions [Member] \| Industrial Solutions [Member]
Segment Reporting Information [Line Items]
Net sales									2,012	2,232	1,967
Automation Solutions [Member] \| Process Control Systems & Solutions [Member]
Segment Reporting Information [Line Items]
Net sales									2,317	2,369	2,121
Operating Segments [Member] \| Automation Solutions [Member]
Segment Reporting Information [Line Items]
Net sales									11,155	12,202	11,441
Earnings before income taxes									1,523	1,947	1,886
Total Assets	14,250				13,996				14,250	13,996	13,720
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Net sales									5,643	6,169	5,982
Earnings before income taxes									1,118	1,271	1,352
Total Assets	4,556				4,347				4,556	4,347	4,496
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Net sales									3,980	4,313	4,454
Earnings before income taxes									801	883	972
Total Assets	3,065				2,885				3,065	2,885	2,936
Operating Segments [Member] \| Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Net sales									1,663	1,856	1,528
Earnings before income taxes									317	388	380
Total Assets	1,491				1,462				1,491	1,462	1,560
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Unallocated pension and postretirement costs									53	108	79
Interest Income (Expense), Nonoperating, Net									(156)	(174)	(159)
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Stock compensation									(110)	(120)	(216)
Earnings before income taxes									(93)	(173)	(275)
Corporate, Non-Segment [Member] \| Corporate and other [Member]
Segment Reporting Information [Line Items]
Total Assets	$ 4,076				$ 2,154				4,076	2,154	2,174
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales									$ (13)	$ 1	$ (15)