Related Parties (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Related Party Transaction [Line Items]
Annual management fee percentage rate	2.50%		2.50%
Annual management fees paid to Fund Manager	$ 271	$ 322	$ 541	$ 644
Percentage of total distributions allocated to Fund Manager	15.00%		15.00%
Fund Manager [Member]
Related Party Transaction [Line Items]
Distributions		$ (42)	$ (48)	$ (100)