Segment Information Geographic Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Geographic Area Information [Line Items]
Net sales	$ 22,317	$ 23,968	$ 23,400
Long-Lived Assets (Year-end)	3,059	3,348	3,300
United States
Geographic Area Information [Line Items]
Net sales	11,007	11,773	11,306
Long-Lived Assets (Year-end)	1,713	1,824	1,879
China
Geographic Area Information [Line Items]
Net sales	1,206	1,424	1,480
Long-Lived Assets (Year-end)	164	326	332
Germany
Geographic Area Information [Line Items]
Net sales	583	629	616
Long-Lived Assets (Year-end)	22	20	19
United Kingdom
Geographic Area Information [Line Items]
Net sales	980	1,042	1,075
Long-Lived Assets (Year-end)	70	77	73
Taiwan
Geographic Area Information [Line Items]
Net sales	725	612	661
Long-Lived Assets (Year-end)	133	141	154
Japan
Geographic Area Information [Line Items]
Net sales	1,789	1,943	1,903
Long-Lived Assets (Year-end)	204	228	209
Other European Countries
Geographic Area Information [Line Items]
Net sales	1,914	1,920	1,936
Long-Lived Assets (Year-end)	186	164	170
Other Foreign
Geographic Area Information [Line Items]
Net sales	4,113	4,625	4,423
Long-Lived Assets (Year-end)	$ 567	$ 568	$ 464