Financial Statement Revision And Summary Of Significant Accounting Policies (Effects Of Adjustment On Operating Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended						12 Months Ended
	Sep. 25, 2011	Jun. 26, 2011	Mar. 27, 2011	Sep. 26, 2010	Jun. 27, 2010	Mar. 28, 2010	Dec. 25, 2011	Dec. 26, 2010	Dec. 27, 2009
Operating income	$ (7,170)	$ 13,551	$ (9,031)	$ 14,201	$ 14,070	$ 5,285	$ 6,493	$ 43,371	$ 41,254
As Previously Reported [Member]
Operating income	(8,603)	12,610	(10,581)	13,062	14,116	5,621		42,648	41,580
Canada Adjustments [Member]
Operating income	797	430	823	719	(391)	(630)		(446)	(1,793)
Discontinued Operations Adjustments [Member]
Operating income	636	511	727	420	345	294		1,169	1,467
As Revised For Revision Adjustments [Member]
Operating income	$ (7,806)	$ 13,040	$ (9,758)	$ 13,781	$ 13,725	$ 4,991		$ 42,202	$ 39,787