Schedule of Long Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 25, 2011
Debt Instrument [Line Items]
Revolving Credit Facility borrowings	$ 300.0	$ 300.0
Other	0.1	0.1
Total debt	300.1	300.1
Current portion of long-term debt
Long-term debt, less current portion	$ 300.1	$ 300.1

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Amount borrowed under the credit facility as of the balance sheet date.

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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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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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