Net Income Per Share (Schedule of Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2018	Apr. 02, 2017
Numerator:
Net income	$ 5,590	$ 15,994
Denominator:
Weighted average common shares - basic (in shares)	31,427	32,944
Potentially dilutive common share equivalent (in shares)	1,233	1,192
Weighted average common shares - dilutive (in shares)	32,660	34,136
Basic net income per share (in dollars per share)	$ 0.18	$ 0.49
Diluted net income per share (in dollars per share)	$ 0.17	$ 0.47
Anti-dilutive employee stock-based awards, excluded (in shares)	773	70