Members' Capital (Narrative) (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Members Capital Account [Line Items]
Potential repurchase price of Units as percentage of holder's capital account	100.00%
Allocation of net income and net loss	100.00%
Other Members [Member]
Members Capital Account [Line Items]
Members capital account, Units issued	2,565,749	2,565,749
Members capital account, Units outstanding	2,565,749	2,565,749	2,551,749
Percentage of fund distributions	99.99%
Other Members [Member] | After Initial Closing Date [Member]
Members Capital Account [Line Items]
Allocation of net income and net loss	99.99%
Managing Member [Member]
Members Capital Account [Line Items]
Allocation of net income and net loss	0.01%
Managing Member [Member] | Until Initial Closing Date [Member]
Members Capital Account [Line Items]
Allocation of net income and net loss	99.00%
Managing Member [Member] | After Initial Closing Date [Member]
Members Capital Account [Line Items]
Percentage of fund distributions	0.01%
Initial Member [Member]
Members Capital Account [Line Items]
Members capital account, Units issued	50
Initial Member [Member] | Until Initial Closing Date [Member]
Members Capital Account [Line Items]
Allocation of net income and net loss	1.00%
Maximum [Member] | Other Members [Member]
Members Capital Account [Line Items]
Members capital account, units authorized	15,000,000