Segment Information Geographic Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Geographic Area Information [Line Items]
Net sales	$ 23,968	$ 23,400	$ 22,835
Long-Lived Assets (Year-end)	3,348	3,300	3,341
United States
Geographic Area Information [Line Items]
Net sales	11,773	11,306	11,353
Long-Lived Assets (Year-end)	1,824	1,879	1,824
China
Geographic Area Information [Line Items]
Net sales	1,424	1,480	1,448
Long-Lived Assets (Year-end)	326	332	171
Germany
Geographic Area Information [Line Items]
Net sales	629	616	576
Long-Lived Assets (Year-end)	20	19	19
United Kingdom
Geographic Area Information [Line Items]
Net sales	1,042	1,075	872
Long-Lived Assets (Year-end)	77	73	109
Taiwan
Geographic Area Information [Line Items]
Net sales	612	661	625
Long-Lived Assets (Year-end)	141	154	169
Japan
Geographic Area Information [Line Items]
Net sales	1,943	1,903	1,816
Long-Lived Assets (Year-end)	228	209	180
Other European Countries
Geographic Area Information [Line Items]
Net sales	1,920	1,936	1,923
Long-Lived Assets (Year-end)	164	170	274
Other Foreign
Geographic Area Information [Line Items]
Net sales	4,625	4,423	4,222
Long-Lived Assets (Year-end)	$ 568	$ 464	$ 595