SHAREHOLDERS' EQUITY (DETAILS) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended			1 Months Ended	6 Months Ended	1 Months Ended	6 Months Ended	1 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Mar. 31, 2012 Series C 6.875% Preferred Stock [Member]	Jun. 30, 2012 Series C 6.875% Preferred Stock [Member]	Mar. 31, 2012 Series A 7.25% Preferred Shares [Member]	Jun. 30, 2012 Series A 7.25% Preferred Shares [Member]	Apr. 30, 2012 Series B 7.50% Preferred Shares [Member]	Jun. 30, 2012 Series B 7.50% Preferred Shares [Member]
Class of Stock [Line Items]
Preferred shares, aggregate liquidation value issued						$ 400,000
Preferred shares, dividend rate							6.875%		7.25%		7.50%
Preferred shares, par value per share							$ 0.0125				$ 0.0125
Preferred shares, liquidation preference per share							$ 25.00
Preferred shares, redemption price per share							$ 25.00				$ 100.00
Preferred shares, number of shares repurchased								6,000,000		2,471,570
Loss on repurchase of preferred shares	9,387	0	14,009	0				5,000		9,000
Preferred shares, aggregate liquidation preference redeemed								150,000
Preferred shares, number of shares outstanding									4,000,000		28,430
Preferred shares, liquidation value outstanding	502,843		502,843		500,000				100,000		3,000
Preferred shares, purchase price per share										$ 102.81
Aggregate cash payment to acquire preferred shares			$ 404,073	$ 0						$ 254,000