Net Income Per Share - Reconciliation used in Computing Basic and Diluted Net Income per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Numerator:
Net income	$ 1,864	$ 1,687
Denominator:
Shares used in computation of basic net income per share (weighted average common shares outstanding)	28,370	27,424
Dilutive potential common shares:
Shares used in computation of diluted net income per share	29,382	28,294
Basic net income per share	$ 0.07	$ 0.06
Diluted net income per share	$ 0.06	$ 0.06
Restricted Stock and RSUs [Member]
Dilutive potential common shares:
Dilutive potential common stocks	316	303
Stock Options [Member]
Dilutive potential common shares:
Dilutive potential common stocks	696	567