Financial Highlights (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Class 0 Units [Member]
Per share operating performance [Abstract]
Net asset value per unit, beginning balance (in dollars per units)	$ 121.13	$ 118.77	$ 114.88	$ 123.17
Net (loss) income: [Abstract]
Net investment loss (in dollars per unit)	$ (0.76)	$ (1.27)	$ (2.50)	$ (3.68)
Net (loss) gain on investments (in dollars per unit)	$ (3.67)	$ (0.60)	$ 4.32	$ (2.59)
Net (loss) income (in dollars per unit)	$ (4.43)	$ (1.87)	$ 1.82	$ (6.27)
Net asset value per unit, ending balance (in dollars per unit)	$ 116.70	$ 116.90	$ 116.70	$ 116.90
Ratios to average members' capital and total return [Abstract]
Total return before Incentive Allocation (in hundredths)	(3.66%)	(1.57%)	1.58%	(5.09%)
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Total return after Incentive Allocation (in hundredths)	(3.66%)	(1.57%)	1.58%	(5.09%)
Net investment loss before Incentive Allocation (in hundredths)	(0.63%)	(1.06%)	(2.11%)	(2.99%)
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Net investment loss after Incentive Allocation (in hundredths)	(0.63%)	(1.06%)	(2.11%)	(2.99%)
Total expenses before Incentive Allocation (in hundredths)	0.69%	1.31%	2.27%	3.83%
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Total expenses after Incentive Allocation (in hundredths)	0.69%	1.31%	2.27%	3.83%
Class 2 Units [Member]
Per share operating performance [Abstract]
Net asset value per unit, beginning balance (in dollars per units)	$ 94.28	$ 94.30	$ 90.29	$ 98.77
Net (loss) income: [Abstract]
Net investment loss (in dollars per unit)	$ (1.06)	$ (1.49)	$ (3.33)	$ (4.43)
Net (loss) gain on investments (in dollars per unit)	$ (2.85)	$ (0.46)	$ 3.41	$ (1.99)
Net (loss) income (in dollars per unit)	$ (3.91)	$ (1.95)	$ 0.08	$ (6.42)
Net asset value per unit, ending balance (in dollars per unit)	$ 90.37	$ 92.35	$ 90.37	$ 92.35
Ratios to average members' capital and total return [Abstract]
Total return before Incentive Allocation (in hundredths)	(4.15%)	(2.07%)	9.00%	(6.50%)
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Total return after Incentive Allocation (in hundredths)	(4.15%)	(2.07%)	9.00%	(6.50%)
Net investment loss before Incentive Allocation (in hundredths)	(1.12%)	(1.57%)	(3.57%)	(4.52%)
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Net investment loss after Incentive Allocation (in hundredths)	(1.12%)	(1.57%)	(3.57%)	(4.52%)
Total expenses before Incentive Allocation (in hundredths)	1.20%	1.81%	3.73%	5.36%
Incentive Allocation (in hundredths)	0.00%	0.00%	0.00%	0.00%
Total expenses after Incentive Allocation (in hundredths)	1.20%	1.81%	3.73%	5.36%