Segment Information Geographic Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Geographic Area Information [Line Items]
Net Sales	$ 37,674	$ 37,179	$ 38,749
Long-Lived Assets (Year-end)	7,872	5,870	6,314
United States
Geographic Area Information [Line Items]
Net Sales	16,214	16,841	16,596
Long-Lived Assets (Year-end)	3,500	2,681	2,762
Germany
Geographic Area Information [Line Items]
Net Sales	3,331	3,375	3,853
Long-Lived Assets (Year-end)	650	680	910
JAPAN
Geographic Area Information [Line Items]
Net Sales	2,262	753	1,064
Long-Lived Assets (Year-end)	253	74	77
Mexico
Geographic Area Information [Line Items]
Net Sales	1,637	1,933	2,001
Long-Lived Assets (Year-end)	708	594	567
Other European Countries
Geographic Area Information [Line Items]
Net Sales	6,860	7,320	8,913
Long-Lived Assets (Year-end)	1,284	1,006	1,064
Other Foreign
Geographic Area Information [Line Items]
Net Sales	7,370	6,957	6,322
Long-Lived Assets (Year-end)	$ 1,477	$ 835	$ 934