Subsequent Event (Details) - USD ($) $ in Millions		12 Months Ended
	Nov. 13, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Information [Line Items]
Business divestitures, net of cash divested		$ 2,202	$ 220	$ 32
Subsequent Event [Member] | Power Solutions
Segment Information [Line Items]
Proceeds from divestitures	$ 13,200
Business divestitures, net of cash divested	$ 11,400