Schedule II-Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 25, 2010
Allowance for doubtful receivables
Movement in Valuation and Qualifying Accounts
Balance at beginning of period	$ 7,555	$ 8,406	$ 5,905
Delta Acquisition			3,124
Charged to profit and loss	1,336	1,627	939
Deductions from reserves	(993)	(2,478)	(1,562)
Balance at close of period	7,898	7,555	8,406
Allowance for deferred income tax asset valuation
Movement in Valuation and Qualifying Accounts
Balance at beginning of period	123,522	208,130	4,529
Delta Acquisition			204,470
Charged to profit and loss	(2,543)	(84,608)	(869)
Balance at close of period	$ 120,979	$ 123,522	$ 208,130