CAPITAL TRANSACTIONS (Details) (USD $)	3 Months Ended			6 Months Ended		0 Months Ended	1 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jan. 31, 2013	Jun. 30, 2014	Jun. 30, 2013	Aug. 05, 2014 Cumulative Redeemable Preferred Stock, Series E [Member]	May 31, 2013 Cumulative Redeemable Preferred Stock, Series E [Member]	Aug. 05, 2014 Cumulative Redeemable Preferred Stock, Series E [Member]	Jun. 30, 2014 Cumulative Redeemable preferred Stock, Series E issuance one [Member]	Jun. 30, 2014 Cumulative Redeemable Preferred Stock, Series E issuance two [Member]	Jun. 30, 2013 Series A And Series B Preferred Stock [Member]
Class of Stock [Line Items]
Redeemable preferred stock, shares issued (in shares)							6,800,000
Redeemable preferred stock, face value							$ 170,000,000
Preferred Stock, Dividend Rate, Percentage (in hundredths)							7.50%
Redeemable preferred stock, liquidation preference per share (in dollars per share)							$ 25.00
Reduction in income per share (in dollars per share)											$ (0.21)
Cash used for redemption of preferred stock											207,000,000
Redemption preference premiums paid	0	19,924,000		0	19,924,000						19,924,000
Proceeds from Issuance of Redeemable Preferred Stock						572,000	164,300,000		12,500,000	13,800,000
Cash on hand paid to redeem preferred stock							42,700,000
Additional shares issued (in shares)						24,000			522,000	578,000
Average cost per share (in dollars per share)								$ 23.78	$ 23.97	$ 23.96
Common shares repurchased (in shares)			3,600,000
Common shares repurchased			42,400,000
Common stock repurchase program			$ 100,000,000