Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Income Statement [Abstract]
Net sales	$ 903,221	$ 859,604	$ 802,957
Cost of goods sold	544,572	521,530	494,907
Gross profit	358,649	338,074	308,050
Selling, general and administrative expenses	182,409	169,473	161,893
Income from operations	176,240	168,601	146,157
Other income (expense), net	348	(241)	(216)
Income before income taxes	176,588	168,360	145,941
Provision for income taxes	69,989	62,311	53,612
Net income	$ 106,599	$ 106,049	$ 92,329
Earnings per share:
Basic	$ 3.14	$ 3.07	$ 2.60
Diluted	$ 3.13	$ 3.07	$ 2.60
Weighted average shares outstanding:
Basic	33,964	34,516	35,466
Diluted	34,052	34,598	35,538