Sales By Product Category Information (Detail) (Sales)	12 Months Ended
	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Product Information [Line Items]
Sales	100.00%	100.00%	100.00%
Supplies
Product Information [Line Items]
Sales	47.20%	46.60%	45.80%
Technology
Product Information [Line Items]
Sales	38.00%	40.60%	41.80%
Furniture And Other
Product Information [Line Items]
Sales	14.80%	12.80%	12.40%