EQUITY (Details) (USD $)	0 Months Ended		3 Months Ended
	Jan. 23, 2014	Mar. 21, 2013	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Equity [Line Items]
Preferred stock, shares issued		5,750,000	5,750,000		5,750,000
Common dividends, declared	$ 0.36		$ 0.36	$ 0.34
Preferred Stock, Dividend Rate, Percentage			7.125%
Preferred Stock, Redemption Price Per Share		$ 25.00
Issuance of preferred stock		$ 138,300,000	$ 0	$ 138,983,000
Convertible Preferred Stock, Terms of Conversion			1.7864
Common Stock, At The Market Stock Offering, Max Possible Gross Proceeds			100,000,000
Common Stock, At the Market Stock Offering, Sales Commision			2.00%
Common Stock, At the Market Stock Offering, Number of Shares Sold			200,000
Proceeds from Issuance of Common Stock			(648,000)	(2,534,000)
Restricted Stock Units (RSUs) [Member]
Equity [Line Items]
Stock-based compensation, issued during period (in shares)			175,096
Stock Options [Member]
Equity [Line Items]
Stock-based compensation, issued during period (in shares)			11,515
At-the-Market Offering, Sales Agents [Member]
Equity [Line Items]
Share Price			$ 27.68
Proceeds from Issuance of Common Stock			4,600,000
Payments of Stock Issuance Costs			100,000
Common Stock, Amount Available for Future Issuance			$ 57,100,000