Convertible Notes Payable Summary of Notes Due 2020 (Details) (Convertible Notes Payable, 4.0% Convertible Senior Notes due December 15, 2020, USD $) In Thousands, unless otherwise specified	Jul. 31, 2013	Dec. 27, 2012
Convertible Notes Payable \| 4.0% Convertible Senior Notes due December 15, 2020
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 190,456
Debt Instrument, Unamortized Discount	16,171
Long-term Debt	(174,285)
Debt Instrument, Convertible, Carrying Amount of Equity Component	$ 43,131	$ 43,100

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The amount of debt discount 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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