Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
Apr. 30, 2008	Sep. 30, 2011	Jun. 30, 2011
Long-term Debt
Principal amount	$ 750
Stated interest rate	6.90%
Debt instrument due date	2018
Effective interest rate	7.00%
Unamortized discount	5.4
Debt Instrument, Frequency of Periodic Payment	semi-annually
Offer to repurchase senior notes, percent of principal amount		101.00%
Fair value		$ 857.4	$ 863.5

Debt Instruments Maturity Date

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- Definition

The price as a percent of the principal amount the company is obligated to repurchase in the event of a change of control followed by a downgrade of the rating of the Company's senior notes.

+ Details

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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+ Details

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Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

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+ Details

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Balance Type:	debit
Period Type:	instant