Leases Future Minimum Capital and Operating Lease Payments and Related Present Value of Capital Lease Payments (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013
Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Capital Leases, 2014	$ 13
Capital Leases, 2015	11
Capital Leases, 2016	8
Capital Leases, 2017	7
Capital Leases, 2018	14
Capital Leases, After 2018	25
Capital Leases, Total minimum lease payments	78
Interest	(13)
Present value of net minimum lease payments	65
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, 2014	300
Operating Leases, 2015	244
Operating Leases, 2016	138
Operating Leases, 2017	95
Operating Leases, 2018	60
Operating Leases, After 2018	71
Operating Leases, Total minimum lease payments	$ 908