Summary of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Earning per share reconciliation
Net income	$ 9,005	$ 5,935
Weighted-average common shares outstanding	76,375	76,401
Earnings per share, basic	$ 0.12	$ 0.08
Net income	$ 9,005	$ 5,935
Weighted-average common shares outstanding	76,375	76,401
Effect of assumed exercise of stock options and RSUs	2,503	2,191
Weighted-average common shares outstanding, assuming dilution	78,878	78,592
Earnings per share, diluted	$ 0.11	$ 0.08
Outstanding options, warrants and RSUs excluded as impact would be antidilutive	492	60
Stock Options
Earning per share reconciliation
Weighted-average effect of dilutive securities	1,444	1,510
RSUs
Earning per share reconciliation
Weighted-average effect of dilutive securities	1,059	681

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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