The Company and Significant Accounting Policies - Reconciliation of Basic and Diluted Income (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:
Net income (loss) applicable to common stockholders	$ (21,384)	$ 7,233	$ (17,268)	$ 5,904
Net income (loss) applicable to common stockholders	(21,384)	7,233	(17,268)	5,904
Denominator:
Weighted average common shares outstanding	87,959,856	85,940,225	87,170,106	85,861,671
Per share:
Net income (loss) per share applicable to common stockholders	$ (0.24)	$ 0.08	$ (0.20)	$ 0.07
Numerator:
Net income (loss) applicable to common stockholders	(21,384)	7,233	(17,268)	5,904
Net income (loss) applicable to common stockholders	$ (21,384)	$ 7,233	$ (17,268)	$ 5,904
Denominator:
Weighted average common shares outstanding	87,959,856	85,940,225	87,170,106	85,861,671
Dilutive securities:
Stock options and restricted stock units		446,430		359,197
Diluted shares outstanding	87,959,856	86,386,655	87,170,106	86,220,868
Per share:
Net income (loss) per share applicable to common stockholders	$ (0.24)	$ 0.08	$ (0.20)	$ 0.07