Cash Management Agreement with Affiliate - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Related Party Transaction [Line Items]
Cash and cash equivalents on deposit with affiliate	$ 5,180,075		$ 5,180,075		$ 9,596,823
Fixed income securities held by affiliate	19,952,245		19,952,245		21,870,890
Advisory fees	$ 11,546	$ 15,594	$ 26,865	$ 30,860
Annual fee			0.20%
Description of daily fee rate calculated and accrued			RJOIM is paid an annual fee, currently 0.20%, calculated and accrued daily at a rate equal to 1/360 of the principal balance.