Financial Highlights (Net Investment Income Ratio To Average Equity) (Details)	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Financial Highlights [Abstract]
Net Investment Income	9.41%	[1],[2]	11.51%	[1],[2]

[1] Average equity is calculated using month end values.

[2] Includes incentive fee in calculation which can vary substantially over periods.