EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Numerator for basic and diluted earnings per share:
Income from continuing operations	$ 155,912	$ 123,339
Discontinued operations	(53)	(489)
Gain on real estate dispositions	43,289	26,184
Net income	199,148	149,034	$ 651,490
Net income attributable to noncontrolling interests	1,021	54
Net income attributable to common stockholders	$ 198,127	$ 148,980
Denominator:
Denominator for basic earnings per share—weighted average shares (in shares)	354,410	335,559
Effect of dilutive securities:
Stock options (in shares)	452	311
Restricted stock awards (in shares)	164	149
OP units (in shares)	2,546	3,183
Denominator for diluted earnings per share—adjusted weighted average shares (in shares)	357,572	339,202
Basic earnings per share:
Income from continuing operations (in usd per share)	$ 0.44	$ 0.37
Net income attributable to common stockholders (in usd per share)	0.56	0.44
Diluted earnings per share:
Income from continuing operations (in usd per share)	0.44	0.36
Net income attributable to common stockholders (in usd per share)	$ 0.55	$ 0.44