EQUITY - Narrative (Details) $ / shares in Units, $ in Thousands				9 Months Ended	12 Months Ended
	Oct. 28, 2016 USD ($) $ / shares shares	Jun. 30, 2016 USD ($)	Jun. 28, 2016 USD ($) shares	Sep. 30, 2016 USD ($) $ / shares shares	Dec. 31, 2015 $ / shares shares	Jul. 31, 2016
Class of Stock [Line Items]
Common stock, shares authorized | shares				500,000,000	500,000,000
Common stock, par value (in dollars per share) | $ / shares				$ 0.01	$ 0.01
Preferred stock, shares authorized | shares				100,000,000	100,000,000
Preferred stock, par value (in dollars per share) | $ / shares				$ 0.01	$ 0.01
Net proceeds from sale of preferred stock | $				$ 72,290
Undesignated preferred stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares				88,600,000
9.25% Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares				2,000,000
Preferred stock, dividend rate (as a percent)				9.25%	9.25%
Preferred stock, liquidation preference (in dollars per share) | $ / shares				$ 25
7.875% Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares				3,000,000
Preferred stock, dividend rate (as a percent)				7.875%	7.875%
Preferred stock, liquidation preference (in dollars per share) | $ / shares				$ 25
Annual dividend rate per share (in dollars per share) | $ / shares				$ 1.96875
7.875% Series B Preferred Stock | Maximum
Class of Stock [Line Items]
Ratio for conversion				5.6497
7.125% Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares				3,400,000
Preferred stock, dividend rate (as a percent)				7.125%	7.125%
Preferred stock, liquidation preference (in dollars per share) | $ / shares				$ 25
Annual dividend rate per share (in dollars per share) | $ / shares				$ 1.78125
7.125% Series C Preferred Stock | Maximum
Class of Stock [Line Items]
Ratio for conversion				5.1440
6.450% Series D Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares				3,000,000
Preferred stock, dividend rate (as a percent)				6.45%
Net proceeds from sale of preferred stock (in shares) | shares			3,000,000
Net proceeds from sale of preferred stock | $			$ 72,300
Underwriting discount and offering-related expenses | $			$ 2,700
Preferred stock, liquidation preference (in dollars per share) | $ / shares				$ 25
Annual dividend rate per share (in dollars per share) | $ / shares				$ 1.6125
6.450% Series D Preferred Stock | Maximum
Class of Stock [Line Items]
Ratio for conversion				3.9216
Operating partnership | Non-controlling Interests in Operating Partnership
Class of Stock [Line Items]
Number of common units of operating partnership owned by unaffiliated third parties | shares				454,965	516,021
Percentage of limited partnership interest in operating partnership (less than)				1.00%	1.00%
Subsequent Event | 9.25% Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized | shares	2,000,000
Payments to redeemable preferred stock | $	$ 50,700
Preferred stock redemption price per share (in dollars per share) | $ / shares	$ 25.00
Leasehold Venture
Class of Stock [Line Items]
Payments to acquire interest in joint venture | $		$ 400
Ownership interest in joint venture (as a percent)						100.00%