Consolidated Statement Of Changes In Shareholders' Equity (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
CHANGE IN SHAREHOLDERS' EQUITY RESULTING FROM OPERATIONS
Net investment income	$ 8,822		$ 12,074		$ 19,782		$ 22,672
Net realized gain (loss) on investments and financial derivatives	(11,280)		(3,916)		(23,068)		7,688
Change in net unrealized gain (loss) on investments and financial derivatives	13,226		(9,479)		46,109		(20,574)
Net increase (decrease) in shareholders' equity resulting from operations	10,768		(1,321)		42,823		9,786
CHANGE IN SHAREHOLDERS' EQUITY RESULTING FROM SHAREHOLDER TRANSACTIONS
Shares issued in connection with incentive fee payment	0		61		0		203
Dividends paid	(11,787)	[1]	(6,757)	[1]	(18,522)	[1]	(28,883)	[1]
Share-based LTIP awards	30		38		58		76
Net decrease in shareholders' equity from shareholder transactions	(11,757)		(6,658)		(18,464)		(28,604)
Net increase (decrease) in shareholders' equity	(989)		(7,979)		24,359		(18,818)
SHAREHOLDERS' EQUITY, BEGINNING OF PERIOD	396,264		392,833		370,916		403,672
SHAREHOLDERS' EQUITY, END OF PERIOD	$ 395,275		$ 384,854		$ 395,275		$ 384,854

[1] For the three month periods ending June 30, 2012 and 2011, dividends totaling $0.70 and $0.40, respectively, per common share and LT IP unit outstanding were declared and paid. For the six month periods ending June 30, 2012 and 2011, dividends totaling $1.10 and $1.71, respectively, per common share and LT IP unit outstanding were declared and paid.