Debt - Fair Value and Future Maturities of Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	Dec. 30, 2012	Dec. 25, 2011
Debt Disclosure [Abstract]
Principal amount outstanding	$ 630.7	$ 631.8
Carrying amount	649.4	654.6
Fair value	690.5	642.7
Long-term debt premium	18.7	22.8
Maturities of Long-term Debt [Abstract]
Maturities of long-term debt in 2013	1.0
Maturities of long-term debt in 2014	1.0
Maturities of long-term debt in 2015	1.0
Maturities of long-term debt in 2016	1.0
Maturities of long-term debt in 2017	$ 626.0

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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.

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

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The fair value amount of long-term debt 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

No definition available.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

+ References

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

+ References

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

+ References

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