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		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Fully diluted (loss) earnings per share
Net income (loss) from continuing operations available to common stockholders	$ 13,611	$ 20,001	$ 75,479	$ 63,999
Net income (loss) for fully diluted shares	$ 21,010	$ 20,001	$ 100,195	$ 87,517
Weighted-average shares:
Common stock outstanding	341,272	321,199	339,845	314,501
Fully diluted earnings (loss) per share from continuing operations	$ 0.04	$ 0.06	$ 0.21	$ 0.20
Continuing Operations [Member]
Fully diluted (loss) earnings per share
Net income (loss) from continuing operations available to common stockholders	$ 13,611	$ 20,001	$ 75,479	$ 63,999
Allocations of net income (loss) to limited partnership interests, net of tax	7,399		24,716	23,518
Net income (loss) for fully diluted shares	$ 21,010	$ 20,001	$ 100,195	$ 87,517
Weighted-average shares:
Common stock outstanding	341,272	321,199	339,845	314,501
Partnership units	180,279		125,824	112,818
RSUs (Treasury stock method)	57	311	168	454
Other	1,376	1,210	1,395	1,297
Fully diluted weighted-average shares of common stock outstanding	522,984	322,720	467,232	429,070
Fully diluted earnings (loss) per share from continuing operations	$ 0.04	$ 0.06	$ 0.21	$ 0.20