Financial Highlights (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Class 0 Units [Member]
Per unit operating performance [Abstract]
Net asset value per unit, beginning balance (in dollars per units)	143.72	159.93	147.34	149.37
Net income (loss) [Abstract]
Net investment loss (in dollars per unit)	(0.89)	(1.01)	(1.74)	(2.05)
Net gain (loss) on investments (in dollars per unit)	2.06	(9.43)	(0.71)	2.17
Net income (loss) (in dollars per unit)	1.17	(10.44)	(2.45)	0.12
Net asset value per unit, ending balance (in dollars per unit)	144.89	149.49	144.89	149.49
Ratios to average members' capital and total return [Abstract]
Total return before Incentive Allocation	0.81%	(6.53%)	(1.66%)	1.88%
Incentive Allocation	0.00%	0.00%	0.00%	(1.80%)
Total return after Incentive Allocation	0.81%	(6.53%)	(1.66%)	0.08%
Net investment loss before Incentive Allocation	(0.63%)	(0.65%)	(1.20%)	(1.32%)
Incentive Allocation	0.00%	0.00%	0.00%	(1.71%)
Net investment loss after Incentive Allocation	(0.63%)	(0.65%)	(1.20%)	(3.03%)
Total expenses before Incentive Allocation	0.75%	0.73%	1.42%	1.46%
Incentive Allocation	0.00%	0.00%	0.00%	1.71%
Total expenses after Incentive Allocation	0.75%	0.73%	1.42%	3.17%
Class 2 Units [Member]
Per unit operating performance [Abstract]
Net asset value per unit, beginning balance (in dollars per units)	106.68	121.12	109.91	113.58
Net income (loss) [Abstract]
Net investment loss (in dollars per unit)	(1.18)	(1.34)	(2.36)	(2.74)
Net gain (loss) on investments (in dollars per unit)	1.52	(7.12)	(0.53)	1.82
Net income (loss) (in dollars per unit)	0.34	(8.46)	(2.89)	(0.92)
Net asset value per unit, ending balance (in dollars per unit)	107.02	112.66	107.02	112.66
Ratios to average members' capital and total return [Abstract]
Total return before Incentive Allocation	0.32%	(6.99%)	(2.63%)	0.84%
Incentive Allocation	0.00%	0.00%	0.00%	(1.65%)
Total return after Incentive Allocation	0.32%	(6.99%)	(2.63%)	(0.81%)
Net investment loss before Incentive Allocation	(1.12%)	(1.15%)	(2.19%)	(2.34%)
Incentive Allocation	0.00%	0.00%	0.00%	(1.62%)
Net investment loss after Incentive Allocation	(1.12%)	(1.15%)	(2.19%)	(3.96%)
Total expenses before Incentive Allocation	1.24%	1.22%	2.41%	2.48%
Incentive Allocation	0.00%	0.00%	0.00%	1.62%
Total expenses after Incentive Allocation	1.24%	1.22%	2.41%	4.10%