Accrued Cost Relating to Retention Agreements (Detail) (CAD) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Apr. 01, 2012	Dec. 30, 2012
Restructuring Cost and Reserve [Line Items]
Cost incurred during the period	9,475	0	18,874
Paid during the period	(15,232)		(5,644)
Accrued as at end of period	7,473		13,230
Termination Costs
Restructuring Cost and Reserve [Line Items]
Cost incurred during the period	6,632		9,016
Paid during the period	(10,894)		(1,458)
Accrued as at end of period	3,296		7,558
Professional Fees and Other
Restructuring Cost and Reserve [Line Items]
Cost incurred during the period	2,543		7,602
Paid during the period	(4,063)		(3,775)
Accrued as at end of period	2,307		3,827
Transition Cost
Restructuring Cost and Reserve [Line Items]
Cost incurred during the period	300		2,256
Paid during the period	(275)		(411)
Accrued as at end of period	1,870		1,845