Restructuring Costs (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)
Restructuring Reserve [Roll Forward]
Beginning restructuring liability			$ 69
Restructuring expense	$ 88	$ 20	216	$ 40
Restructuring utilized/paid			126
Ending restructuring liability	159		$ 159
Total number of employee workforce reductions			3,300
Cost of Sales [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	6		$ 15
Severance and benefits [Member]
Restructuring Reserve [Roll Forward]
Beginning restructuring liability			62
Restructuring expense			184
Restructuring utilized/paid			92
Ending restructuring liability	154		154
Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Beginning restructuring liability			7
Restructuring expense			32
Restructuring utilized/paid			34
Ending restructuring liability	5		5
Automation Solutions [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	76	15	182	26
Commercial & Residential Solutions [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	9	5	26	13
Climate Technologies [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	5	4	14	8
Tools & Home Products [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	4	1	12	5
Corporate [Member]
Restructuring Reserve [Roll Forward]
Restructuring expense	$ 3	$ 0	$ 8	$ 1
Forecast [Member]
Restructuring Reserve [Roll Forward]
Expected fiscal year restructuring expense					$ 300
Increase (decrease) in expected restructuring related costs					$ 20