Trading Companies (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Trading Companies [Abstract]
Trading quarterly advisor incentive fee, on trading profits (in hundredths)	20.00%mflv_IncentiveFeeRateTradingAdvisor
Partnership's investment in affiliated Trading Companies [Line Items]
Average daily funds held basis (in hundredths)	100.00%
Interest income basis spread deduction from 4-week U.S. Treasury bill discount rate (in hundredths)	0.15%
Trading Company brokerage fees and transaction cost rate basis as a percentage charged to retail commodity customers (in hundredths)	100.00%mflv_PercentageOfBrokerageFee
Trading company monthly administrative fee (in hundredths)	0.0292%
Trading company annual administrative fee rate (in hundredths)	0.35%
Augustus I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	29.60%	19.60%
Fair Value	$ 3,935,697	$ 4,318,716
Partnership's pro rata Net Income/(Loss)	160,360	(169,072)
Partnership's Management Fees	58,939	66,017
Partnership's Incentive Fees	25,153	13,378
Partnership's Administrative Fees	13,752	15,404
TT II, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	25.30%	28.20%
Fair Value	3,356,258	6,221,176
Partnership's pro rata Net Income/(Loss)	601,930	(148,361)
Partnership's Management Fees	47,124	141,129
Partnership's Incentive Fees	61,805	0
Partnership's Administrative Fees	13,195	28,226
Boronia I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	22.40%	10.20%
Fair Value	2,976,216	2,237,602
Partnership's pro rata Net Income/(Loss)	523,865	288,580
Partnership's Management Fees	47,139	43,450
Partnership's Incentive Fees	130,966	72,193
Partnership's Administrative Fees	8,799	7,732
Rotella I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	0.00%	18.30%
Fair Value	0	4,039,384
Partnership's pro rata Net Income/(Loss)	252,994	294,968
Partnership's Management Fees	36,089	41,744
Partnership's Incentive Fees	64,058	25,511
Partnership's Administrative Fees	12,631	14,610
Kaiser I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	0.00%	8.40%
Fair Value	0	1,861,138
Partnership's pro rata Net Income/(Loss)	(222,158)	250,659
Partnership's Management Fees	19,534	40,439
Partnership's Incentive Fees	0	30,404
Partnership's Administrative Fees	3,419	7,070
WNT I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)	0.00%	17.30%
Fair Value	0	3,816,627
Partnership's pro rata Net Income/(Loss)	(79,472)	532,962
Partnership's Management Fees	14,154	67,855
Partnership's Incentive Fees	0	61,790
Partnership's Administrative Fees	3,303	15,833
Chesapeake I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)		0.00%
Fair Value		0
Partnership's pro rata Net Income/(Loss)		52,305
Partnership's Management Fees		17,564
Partnership's Incentive Fees		0
Partnership's Administrative Fees		6,147
GLC I, LLC [Member]
Partnership's investment in affiliated Trading Companies [Line Items]
% of Partnership's Partners' Capital (in hundredths)		0.00%
Fair Value		0
Partnership's pro rata Net Income/(Loss)		13,652
Partnership's Management Fees		675
Partnership's Incentive Fees		0
Partnership's Administrative Fees		$ 542

The percentage of average daily funds held used in a calculation for revenue recognition.

No definition available.

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- Definition

Rate basis on trading profits for incentive obligation payments in cash or stock during the period to a limited liability corporation managing member or limited partnership general partner.

+ References

No definition available.

+ Details

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- Definition

The percentage rate deducted from the reference rate as stated in the agreement and used to compute the variable rate for interest income credit. For instance, for average deposits held, the monthly average 4-week U.S. Treasury bill discount reference rate, less an agreed upon percentage.

+ References

No definition available.

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- Definition

Value of the investment at close of period expressed as a percentage of partners' capital. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

No definition available.

+ Details

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- Definition

The percentage of brokerage fees paid on a half-turn basis of the rates charged retail commodity customers and parties that are not clearinghouse members.

+ References

No definition available.

+ Details

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- Definition

The annual administrative fee rate payable by the trading companies to the general partner.

+ References

No definition available.

+ Details

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- Definition

The monthly administrative fee rate payable by the trading companies to the general partner.

+ References

No definition available.

+ Details

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- Definition

Amount of Equity in net profit and loss for the period. Give totals for each group. If operations of any controlled companies are different in character from those of the company, group such affiliates (1) within divisions and (2) by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 6

-Subparagraph (SX 210.12-14)

-URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611322-123010

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph 2,6

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column C

-Article 12

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- Definition

Value of the investment at close of period. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column E

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611322-123010

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph 2

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph 3

-Article 12

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- Definition

Amount paid to managing member or general partner, affiliate of managing member or general partner, or affiliate of limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Amount paid for incentive rights held by the managing member or general partner, of limited liability company (LLC) or limited partnership (LP).

+ References

+ Details

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- Definition

Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

+ References

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