Convertible Notes (Details 1) (Convertible Senior Notes Due 2015 [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Oct. 01, 2011	Oct. 02, 2010	Oct. 01, 2011	Oct. 02, 2010
Convertible Senior Notes Due 2015 [Member]
Effective interest rate, Contractual interest expense and Amortization of debt discount
Effective interest rate	8.10%	8.10%	8.10%	8.10%
Contractual interest expense	$ 2,289	$ 2,289	$ 6,687	$ 2,716
Amortization of debt discount	$ 3,453	$ 3,196	$ 10,166	$ 3,788

The component of interest expense representing the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate caption: Noncash Interest Expense.

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

-Publisher FASB

-Name Accounting Standards Codification

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