Debt and Financing Arrangements - Components of Net Financing Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Debt Disclosure [Abstract]
Interest expense, net of capitalized interest costs	$ 72	$ 63	$ 215	$ 176
Banking fees and bond cost amortization	6	5	18	14
Interest income	(3)	(3)	(7)	(8)
Net foreign exchange results for financing activities	0	2	(11)	(4)
Net financing charges	$ 75	$ 67	$ 215	$ 178