Debt and Financing Arrangements Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Debt Instrument [Line Items]
Other Long-term Debt	$ 42	$ 42
Capital lease obligations	55	65
Long-term Debt and Capital Lease Obligations, Including Current Maturities	6,497	5,379
Less: current portion	140	819
Net long-term debt	6,357	4,560
Floating Rate Notes Due in 2014
Debt Instrument [Line Items]
Gross long-term debt	0	350
1.75 % Due in 2014
Debt Instrument [Line Items]
Gross long-term debt	0	452
7.7 % Due in 2015
Debt Instrument [Line Items]
Gross long-term debt	125	125
5.5 % Due in 2016
Debt Instrument [Line Items]
Gross long-term debt	802	802
7.125 % Due in 2017
Debt Instrument [Line Items]
Gross long-term debt	156	159
2.6 % Due in 2017
Debt Instrument [Line Items]
Gross long-term debt	400	400
2.355 % Due in 2017
Debt Instrument [Line Items]
Gross long-term debt	46	46
1.4% Due in 2018
Debt Instrument [Line Items]
Gross long-term debt	298	0
5.0 % Due in 2020
Debt Instrument [Line Items]
Gross long-term debt	499	498
4.25% Due in 2021
Debt Instrument [Line Items]
Gross long-term debt	498	497
3.75 % Due in 2022
Debt Instrument [Line Items]
Gross long-term debt	448	448
3.625% Due in 2024
Debt Instrument [Line Items]
Gross long-term debt	500	0
6.0 % Due in 2036
Debt Instrument [Line Items]
Gross long-term debt	395	395
5.7 % Due in 2041
Debt Instrument [Line Items]
Gross long-term debt	299	299
5.25 % Due in 2042
Debt Instrument [Line Items]
Gross long-term debt	250	250
4.625% Due in 2044
Debt Instrument [Line Items]
Gross long-term debt	447	0
6.95 % Due in 2046
Debt Instrument [Line Items]
Gross long-term debt	125	125
4.95% Due in 2064
Debt Instrument [Line Items]
Gross long-term debt	449	0
Euro
Debt Instrument [Line Items]
Gross long-term debt	$ 663	$ 426