Consolidated Statement Of Assets, Liabilities And Equity (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Investments at value, cost	$ 1,688,257	$ 1,328,153
Financial derivatives–assets, at fair value Net cost	50,533	65,860
Repurchase agreements, cost	27,943	13,650
Investments sold short at value, proceeds	(847,602)	(621,048)
Financial derivatives–liabilities, at fair value Net proceeds	(29,746)	(13,171)
Securitized debt proceeds	$ (980)	$ (1,311)
Common stock, par value
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	25,428,186	20,370,469
Common stock, shares outstanding	25,428,186	20,370,469