Earnings Per Share - Computation of Basic and Diluted Net Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income	$ 63,015	$ 47,282
Less: income allocable to participating securities	(27)	(55)
Income allocable to common shares	62,988	47,227
Add back: undistributed earnings allocable to participating securities	27	55
Less: undistributed earnings reallocated to participating securities	(27)	(54)
Numerator for diluted earnings per share	$ 62,988	$ 47,228
Denominator:
Basic weighted average shares outstanding	57,655	57,357
Dilutive effect of unvested restricted stock	785	959
Diluted weighted average shares outstanding	58,440	58,316
Earnings per share:
Earnings per share, basic	$ 1.09	$ 0.82
Earnings per share, diluted	$ 1.08	$ 0.81

Undistributed earnings loss reallocated to participating securities diluted.

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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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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