Other Financial Data (Narrative) (Details) (USD $) In Millions	Sep. 30, 2011
Other Financial Data [Abstract]
Approximate annual rentals under noncancellable long-term leases, exclusive of maintenance, taxes, insurance and other operating costs in 2012	$ 245
Approximate annual rentals under noncancellable long-term leases, exclusive of maintenance, taxes, insurance and other operating costs in 2013	179
Approximate annual rentals under noncancellable long-term leases, exclusive of maintenance, taxes, insurance and other operating costs in 2014	118
Approximate annual rentals under noncancellable long-term leases, exclusive of maintenance, taxes, insurance and other operating costs in 2015	78
Approximate annual rentals under noncancellable long-term leases, exclusive of maintenance, taxes, insurance and other operating costs in 2016	$ 54

Other Financial Data [Abstract]

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph b(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

+ References

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the third year of the balance sheet date relating to leases defined as operating.

+ References

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

+ References

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