Net Income (Loss) Per Share - Reconciliation of Earnings Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2009
Numerator:
Income (loss) from continuing operations	$ 1,205	$ (2,990)	$ 4,234	$ (5,517)
Gain from discontinued operations, net of tax	0	0	0	153	187
Net income (loss) used in computing basic and diluted net income (loss) per share	$ 1,205	$ (2,990)	$ 4,234	$ (5,364)
Denominator:
Shares used in computation of basic net income (loss) per share (weighted average common shares outstanding)	28,558	27,658	28,047	27,885
Dilutive potential common shares:
Shares used in computation of diluted net income (loss) per share	29,653	27,658	29,205	27,885
Basic net income (loss) per share from:
Continuing operations	$ 0.04	$ (0.11)	$ 0.15	$ (0.20)
Discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.01
Total	$ 0.04	$ (0.11)	$ 0.15	$ (0.19)
Diluted net income (loss) per share:
Continuing operations	$ 0.04	$ (0.11)	$ 0.14	$ (0.20)
Discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.01
Total	$ 0.04	$ (0.11)	$ 0.14	$ (0.19)
Restricted Stock and RSUs [Member]
Dilutive potential common shares:
Dilutive potential common shares	302	0	333	0
Stock Options [Member]
Dilutive potential common shares:
Dilutive potential common shares	793	0	825	0