EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Numerator for basic and diluted earnings per share:
Income from continuing operations attributable to common stockholders, including real estate dispositions	$ 149,570	$ 45,235	$ 442,349	$ 279,681
Discontinued operations	(118)	(22,383)	(755)	13,434
Net income attributable to common stockholders	$ 149,452	$ 22,852	$ 441,594	$ 293,115
Denominator:
Denominator for basic earnings per share—weighted average shares (in shares)	350,274	332,491	341,610	329,440
Effect of dilutive securities:
Stock options (in shares)	847	307	594	401
Restricted stock awards (in shares)	193	22	168	49
OP units (in shares)	2,872	3,518	2,980	3,320
Denominator for diluted earnings per share—adjusted weighted average shares (in shares)	354,186	336,338	345,352	333,210
Basic earnings per share:
Income from continuing operations attributable to common stockholders, including real estate dispositions (in usd per share)	$ 0.43	$ 0.14	$ 1.29	$ 0.85
Discontinued operations (in usd per share)	0.00	(0.07)	0.00	0.04
Net income attributable to common stockholders (in usd per share)	0.43	0.07	1.29	0.89
Diluted earnings per share:
Income from continuing operations attributable to common stockholders, including real estate dispositions (in usd per share)	0.42	0.14	1.28	0.84
Discontinued operations (in usd per share)	0.00	(0.07)	0.00	0.04
Net income attributable to common stockholders (in usd per share)	$ 0.42	$ 0.07	$ 1.28	$ 0.88