Debt (Details 1) (Convertible Senior Notes Due 2015 [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Convertible Senior Notes Due 2015 [Member]
Effective interest rate and components of interest expense of 2015 notes
Effective interest rate	8.10%	8.10%	8.10%
Contractual interest expense	$ 9,332	$ 9,157	$ 9,157
Amortization of debt discount	17,674	16,007	14,758
Total Interest Expense	$ 27,006	$ 25,164	$ 23,915

Interest expense related to convertible debt instruments which has been recognized for the period, for the contractual interest coupon.

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

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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

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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