Earnings Per Share - Schedule of Computation of Basic Earnings per Share and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Numerator:
Net income	$ 21,787	$ 26,060	$ 23,143	$ 21,339	$ 18,656	$ 24,536	$ 23,244	$ 23,551	$ 92,329	$ 89,987	$ 81,920
Denominator:
Weighted average basic shares outstanding									35,466	36,052	36,347
Effect of compensation awards									72	138	277
Weighted average diluted shares outstanding									35,538	36,190	36,624
Earnings Per Share:
Basic									$ 2.60	$ 2.50	$ 2.25
Diluted	$ 0.62	$ 0.73	$ 0.65	$ 0.60	$ 0.52	$ 0.68	$ 0.64	$ 0.64	$ 2.60	$ 2.49	$ 2.24