Computation of Basic and Diluted Net Loss Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator:
Income (loss) from continuing operations	$ (9,363)	$ 723	$ (29,887)	$ (14,711)
Income from discontinued operations, net of tax (including gain on disposal of $636, net of tax, for the nine months ended September 30, 2012)				170
Net income (loss)	$ (9,363)	$ 723	$ (29,887)	$ (14,541)
Denominator:
Basic	31,184,958	30,215,144	30,848,478	27,838,292
Diluted	31,184,958	30,611,304	30,848,478	27,838,292
Basic and diluted net income (loss) per share:
Continuing operations	$ (0.30)	$ 0.02	$ (0.97)	$ (0.53)
Discontinued operations				$ 0.01
Net income (loss)	$ (0.30)	$ 0.02	$ (0.97)	$ (0.52)