NET INCOME PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 26, 2014	Sep. 27, 2013
Earnings Per Share [Abstract]
Net income	$ 20,910	$ 18,952	$ 38,650	$ 30,412
Weighted average number of common shares used in basic net income per common share	40,793	40,330	40,701	40,085
Dilutive effect of outstanding stock options and non-vested restricted stock	245	340	270	310
Weighted average number of common shares used in diluted net income per common share	41,038	40,670	40,971	40,395
Net income per common share:
Basic (in dollars per share)	$ 0.51	$ 0.47	$ 0.95	$ 0.76
Diluted (in dollars per share)	$ 0.51	$ 0.47	$ 0.94	$ 0.75
Anti-dilutive shares	97	0	35	0