Segment Information Geographic Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Geographic Area Information [Line Items]
Net Sales	$ 30,172	$ 20,837	$ 17,100
Long-Lived Assets (Year-end)	6,121	5,632	3,683
United States
Geographic Area Information [Line Items]
Net Sales	14,495	9,633	8,982
Long-Lived Assets (Year-end)	3,155	2,880	2,056
CHINA
Geographic Area Information [Line Items]
Net Sales	2,046	1,620	1,350
Long-Lived Assets (Year-end)	535	484	415
Germany
Geographic Area Information [Line Items]
Net Sales	1,779	1,430	911
Long-Lived Assets (Year-end)	290	287	304
United Kingdom
Geographic Area Information [Line Items]
Net Sales	928	291	309
Long-Lived Assets (Year-end)	109	103	4
JAPAN
Geographic Area Information [Line Items]
Net Sales	1,816	1,805	315
Long-Lived Assets (Year-end)	180	188	8
Mexico
Geographic Area Information [Line Items]
Net Sales	840	639	635
Long-Lived Assets (Year-end)	489	457	368
Other European Countries
Geographic Area Information [Line Items]
Net Sales	2,860	1,817	1,961
Long-Lived Assets (Year-end)	542	448	276
Other Foreign
Geographic Area Information [Line Items]
Net Sales	5,408	3,602	2,637
Long-Lived Assets (Year-end)	$ 821	$ 785	$ 252