Debt (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 25, 2012	Dec. 27, 2011
Summary of estimated fair value of debt facilities
Fair value	$ 593,468	$ 376,856
Carrying value	564,063	372,700
Term Loan [Member]
Summary of estimated fair value of debt facilities
Fair value	376,868
Carrying value	374,063
Senior Notes [Member]
Summary of estimated fair value of debt facilities
Fair value	216,600
Carrying value	190,000
Old Term Loan [Member]
Summary of estimated fair value of debt facilities
Fair value		197,700
Carrying value		197,700
Senior Subordinated Notes [Member]
Summary of estimated fair value of debt facilities
Fair value		$ 179,156