Earnings Per Share - Calculation of Fully Diluted Earnings Per Share from Discontinued 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 discontinued operations available to common stockholders		$ 15,038		$ 29,814
Weighted-average shares:
Common stock outstanding	341,272	321,199	339,845	314,501
Discontinued Operations [Member]
Fully diluted (loss) earnings per share
Net income (loss) from discontinued operations available to common stockholders		$ 15,038		$ 29,814
Allocations of net income (loss) to limited partnership interests, net of tax				7,034
Net income (loss) for fully diluted shares		$ 15,038		$ 36,848
Weighted-average shares:
Common stock outstanding		321,199		314,501
Partnership units				112,818
RSUs (Treasury stock method)		311		454
Other		1,210		1,297
Fully diluted weighted-average shares of common stock outstanding		322,720		429,070
Fully diluted earnings (loss) per share from discontinued operations		$ 0.05		$ 0.09