Members' Capital (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Other Members Capital Account [Line Items]
Members capital account, Units issued	13,560,188	13,560,188
Members capital account, Units outstanding	13,560,188	13,560,188	13,560,188
Other Members capital account, Units authorized	15,000,000	15,000,000
Potential repurchase price of Units as a percentage of holder's capital account	100.00%
Distributions declared		$ 4,068
Other Members [Member]
Other Members Capital Account [Line Items]
Members capital account, Units outstanding	13,560,188	13,560,188		13,560,188
Allocation of net income, net losses and distribution allocation percentage	92.50%
Distributions declared		$ 4,068
Managing Member [Member]
Other Members Capital Account [Line Items]
Members capital account, Units issued	50	50
Allocation of net income, net losses and distribution allocation percentage	7.50%