Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2018	Jun. 28, 2017	Jun. 27, 2018	Jun. 28, 2017
Earnings Per Share [Abstract]
Net income	$ 11,626	$ 8,749	$ 21,385	$ 17,122
Weighted average shares outstanding - basic (in shares)	63,644	69,407	64,038	70,205
Effect of dilutive share-based compensation awards	2,484	2,254	2,514	2,254
Weighted average shares outstanding - diluted (in shares)	66,128	71,661	66,552	72,459
Basic net income per share	$ 0.18	$ 0.13	$ 0.33	$ 0.24
Diluted net income per share	$ 0.18	$ 0.12	$ 0.32	$ 0.24
Antidilutive share-based compensation awards (in shares)	1	606	1	606