Option Activity and Changes (Detail) (USD $)	3 Months Ended
	Mar. 29, 2014
Shares
Options outstanding at December 31, 2013	2,637,969
Options granted	48,000
Options cancelled and forfeited	(42,687)
Options exercised	(41,836)
Options outstanding at March 29, 2014	2,601,446
Vested and expected to vest at March 29, 2014	2,418,134
Options exercisable at March 29, 2014	1,381,138
Weighted Average Exercise Price
Options outstanding at December 31, 2013	$ 8.53
Options granted	$ 8.49
Options cancelled and forfeited	$ 7.94
Options exercised	$ 4.58
Options outstanding at March 29, 2014	$ 8.61
Vested and expected to vest at March 29, 2014	$ 8.78
Options exercisable at March 29, 2014	$ 10.45