Income Tax Uncertainties (Narrative) (Details) (USD $) In Millions	9 Months Ended
Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2009
Income Tax Uncertainties
Unrecognized tax benefits	$ 73	$ 75	$ 73	$ 81
Unrecognized tax benefits, recorded	47
Unrecognized tax benefits, not recorded	26
Accruals for penalties	5
Accruals for interest	15
Favorable impact if unrecognized tax benefits were recognized	36
Reduction of unrecognized tax benefits	$ (6)

Unrecognized Tax Benefits Included in Consolidated Financial Statement

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Unrecognized Tax Benefits Not Included In Consolidated Financial Statement

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- Details

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

This element represents the amount of statutory penalties accrued as of the date of the statement of financial position for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
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- Definition

This element represents the amount of interest expense accrued as of the date of the statement of financial position for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph c
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-Publisher FASB
-Name FASB Interpretation (FIN)
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- Definition

The net amount of all increases and decreases in unrecognized tax benefits for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Publisher FASB
-Name FASB Interpretation (FIN)
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-Paragraph 21
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-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.

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