Stockholders' Equity - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income	$ 48,545	$ 42,402
Denominator:
Basic weighted average shares outstanding	115,663,366	116,259,058
Effect of dilutive securities:
Diluted weighted average shares outstanding	116,017,400	116,647,442
Basic earnings per share	$ 0.42	$ 0.37
Diluted earnings per share	$ 0.42	$ 0.36
Stock appreciation rights [Member]
Effect of dilutive securities:
Dilutive securities	207,060	181,446
Restricted stock [Member]
Effect of dilutive securities:
Dilutive securities	146,974	206,938

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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