PREFERRED STOCK - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	Sep. 15, 2015	Mar. 31, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Depositary Shares, Liquidation Preference Per Share	$ 100.00
Series A preferred stock
Class of Stock [Line Items]
Preferred stock, authorized (in shares)		1,000,000	1,000,000
Preferred stock, issued (in shares)		770,000	770,000
Depositary shares (in shares)	7,700,000
Preferred stock, dividend rate	5.25%
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Issuance of preferred stock (in dollars per share)	$ 100.00
Gross proceeds from issuance of preferred stock	$ 770.0
Preferred stock, liquidation preference (in dollars per share)	$ 1,000
Series A preferred stock | Minimum
Class of Stock [Line Items]
Common stock issuable upon conversion (in shares)	5.8716
Series A preferred stock | Maximum
Class of Stock [Line Items]
Common stock issuable upon conversion (in shares)	7.3394