Interest Rate Swap, Target Interest Rate Percentage On Hedging Activity

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- Definition

Line Of Credit Facililty Commitment Fee

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- Definition

Line Of Credit Facility Covenant Minimum Collateral Percentage

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- Definition

Line Of Credit Facility Incremental Borrowing Capacity

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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Description of a short-term or long-term contractual arrangement with a lender, including letter of credit, standby letter of credit, and revolving credit arrangements, under which borrowings can be made up to maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line of credit.

+ References

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- Definition

Increase for additional borrowings on the credit facility during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 08

-Paragraph f

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

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Number of interest rate derivative instruments held by the entity at the reporting date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

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Long-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended					9 Months Ended	12 Months Ended			12 Months Ended
	Sep. 30, 2011	Sep. 30, 2011 3.6% Interest Rate Swaps Due 2014 [Member]	Sep. 30, 2011 3.4% Interest Rate Swaps Due 2014 [Member]	Oct. 31, 2007 2007 Credit Facility [Member]	Nov. 30, 2008 2008 Credit Facility [Member]	Jun. 30, 2011 2011 Credit Facility [Member]	Sep. 30, 2011 2011 Credit Facility [Member]	Sep. 30, 2011 2011 Credit Facility [Member] Maximum [Member]	Sep. 30, 2011 2011 Credit Facility [Member] Minimum [Member]	Sep. 30, 2011 Leverage Ratio [Member]	Sep. 30, 2011 Debt To Capitalization Ratio [Member]	Sep. 30, 2011 Interest Expense Coverage Ratio [Member]
Credit facility capacity				$ 300	$ 280			$ 1,100	$ 750
Incremental commitment							350
Funds available under credit facility							227
2011 Credit Agreement, description	Borrowings under the 2011 Credit Agreement bear interest of the Eurodollar rate plus a margin of 2.50%.
2011 Credit Agreement, commitment fee (per annum)							1.00%
Standby letters of credit							3.4
Various financial covenants										ratio of 4.0 to 1.0	ratio of 0.5 to 1.0	ratio of 3.0 to 1.0
Minimum collateral percentage	150.00%
Number of interest rate swap agreements	4
Notional interest rate swap agreements	50.0
Interest rate fixed as result of interest rate swap hedges		3.60%	3.40%
Additional funds borrowed						$ 0