Earnings Per Share - Calculation of Fully Diluted Earnings Per Share from Continuing Operations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Fully diluted (loss) earnings per share
Net income (loss) from continuing operations available to common stockholders	$ 61,868	$ 43,998
Net income (loss) for fully diluted shares	$ 90,765	$ 64,771
Weighted-average shares:
Common stock outstanding	338,403	307,728
Fully diluted earnings (loss) per share from continuing operations	$ 0.18	$ 0.14
Continuing Operations [Member]
Fully diluted (loss) earnings per share
Net income (loss) from continuing operations available to common stockholders	$ 61,868	$ 43,998
Allocations of net income (loss) to limited partnership interests, net of tax	28,897	20,773
Net income (loss) for fully diluted shares	$ 90,765	$ 64,771
Weighted-average shares:
Common stock outstanding	338,403	307,728
Partnership units	176,072	169,218
RSUs (Treasury stock method)	179	604
Other	1,412	1,385
Fully diluted weighted-average shares of common stock outstanding	516,066	478,935
Fully diluted earnings (loss) per share from continuing operations	$ 0.18	$ 0.14

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