Other Income (Expense), Net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 25, 2010
Other Income (Expense), Net [Abstract]
Interest income	$ 847	$ 711	$ 829
Environmental expense, non-operating properties	(1,128)	(330)	(3,467)
Other	820	1,531	(12)
Other income (expense), net	$ 539	$ 1,912	$ (2,650)