Reconciliation of Average Number of Common Shares and Common Share Equivalents Outstanding (Detail) - shares	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Average number of common shares outstanding	43,664,000	44,956,000	46,039,000
Incremental shares from assumed exercises of stock options	149,000	213,000	171,000
Average number of common shares and common share equivalents outstanding	43,813,000	45,169,000	46,210,000