EQUITY (Details) (USD $)	3 Months Ended	12 Months Ended	3 Months Ended	0 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Mar. 03, 2015	Jan. 01, 2015
Equity
Common stock, shares authorized	500,000,000	500,000,000
Common stock, par value (in dollars per share)	$ 0.01	0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, par value (in dollars per share)	$ 0.01	0.01
Preferred stock, liquidation preference (in dollars per share)	$ 25
9.25% Series A Preferred Stock
Equity
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, dividend rate (as a percent)	9.25%	9.25%
Annual dividend rate per share (in dollars per share)	$ 2.3125
9.25% Series A Preferred Stock | Maximum | Change in control provision
Equity
Ratio for conversion	5.92417
7.875% Series B Preferred Stock
Equity
Preferred stock, shares authorized	3,000,000	3,000,000
Preferred stock, dividend rate (as a percent)	7.875%	7.875%
Annual dividend rate per share (in dollars per share)	$ 1.96875
7.875% Series B Preferred Stock | Maximum | Change in control provision
Equity
Ratio for conversion	5.6497
7.125% Series C Preferred Stock
Equity
Preferred stock, shares authorized	3,400,000	3,400,000
Preferred stock, dividend rate (as a percent)	7.125%	7.125%
Annual dividend rate per share (in dollars per share)	$ 1.78125
7.125% Series C Preferred Stock | Maximum | Change in control provision
Equity
Ratio for conversion	5.1440
Common Stock
Equity
Common stock, shares authorized	500,000,000
Common stock, par value (in dollars per share)	$ 0.01
Shares of common stock issued to redeem common units	20,691		126,155
Equity-based compensation (in shares)	257,885
Restricted stock, shares withheld to cover employee tax obligations	36,116
Common Stock | Executive officers and employees
Equity
Equity-based compensation (in shares)				303,915
Performance-Based | Restricted Stock Awards
Equity
Vested (in shares)	128,185				128,185
Expired (in shares)	46,030