Segment Information - Geographic Information (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	$ 16,526	$ 17,439	$ 16,213
Long-lived assets	1,671	1,683
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	6,435	6,376	6,221
Long-lived assets	504	474
Mexico
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	2,709	2,668	2,595
Long-lived assets	177	161
Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	435	537	602
Long-lived assets	32	31
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	7,785	7,664	7,290
Long-lived assets	713	666
Germany
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	1,463	1,761	1,930
Long-lived assets	195	197
Czech Republic
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	1,431	1,663	1,398
Other EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	5,616	5,892	5,476
Long-lived assets	538	565
EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	6,675	7,436	7,044
Long-lived assets	733	762
Thailand
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	614	615	409
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	529	716	264
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	529	562	597
Other Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	668	768	859
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	2,337	2,659	2,129
Long-lived assets	225	255
Intersegment Eliminations
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	(271)	(320)	(250)
Intersegment Eliminations | Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	(1,794)	(1,917)	(2,128)
Intersegment Eliminations | EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	(1,835)	(1,880)	(1,760)
Intersegment Eliminations | Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	$ (3)	$ (2)	$ 0