Earnings Per Share - Computation of Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income	$ 24,057	$ 10,151
Denominator:
Weighted-average shares outstanding—basic	45,501	43,906
Effect of dilutive securities:
Options to purchase common stock	2,447	2,952
Employee stock purchase plan shares	116	122
Restricted stock	249	334
Weighted-average shares outstanding—diluted	48,313	47,314
Basic EPS	$ 0.53	$ 0.23
Diluted EPS	$ 0.50	$ 0.21
Anti-dilutive equity awards under stock-based award plans excluded from the determination of diluted EPS	388	818

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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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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