Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 1,100	$ 976	$ 695
Other Comprehensive Income (Loss), Net of Tax
Foreign currency translation adjustments	11	(50)	(692)
Defined benefit pension and postretirement plans	179	(141)	(36)
Cash flow hedges	17	1	(9)
Other Comprehensive Income (Loss), Net of Tax	206	(191)	(737)
Comprehensive Income (Loss)	$ 1,306	$ 786	$ (42)