Ceres Tactical Global 10-Q 13 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Entity Registrant Name	MORGAN STANLEY SMITH BARNEY SPECTRUM CURRENCY & COMMODITY L.P.
Entity Central Index Key	1097396
Current Fiscal Year End Date	-19
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	1,523,182.19

Statements_of_Financial_Condit

Statements of Financial Condition (USD $)	Mar. 31, 2015	Dec. 31, 2014
ASSETS
Interest receivable	$72	$61
Total Assets	14,078,876	14,172,143
Liabilities:
Redemptions payable	247,857	238,966
Accrued incentive fees	106,486	108,183
Accrued ongoing placement agent fees	22,565	22,139
Accrued administrative fees	18,052	17,712
Accrued management fees	16,924	15,812
Total Liabilities	411,884	402,812
Partners' Capital:
Limited Partners	13,514,218	13,623,087
General Partner	152,774	146,244
Total Partners' Capital	13,666,992	13,769,331
Total Liabilities and Partners' Capital	14,078,876	14,172,143
NET ASSET VALUE PER UNIT	$8.87	$8.49
Cambridge Master Fund [Member]
ASSETS
Investments	14,078,804	12,289,754
Total Assets	40,423,057	39,046,641
Liabilities:
Total Liabilities	63,431	48,456
Partners' Capital:
Limited Partners	40,359,626	38,998,185
General Partner	0	0
Total Partners' Capital	40,359,626	38,998,185
Total Liabilities and Partners' Capital	40,423,057	39,046,641
KR Master Fund [Member]
ASSETS
Redemptions receivable		$1,882,328

Statements_of_Financial_Condit1

Statements of Financial Condition (Parenthetical)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Limited Partners, Units	1,523,182.19	1,604,009.85
General Partner, Units	17,219.12	17,219.12

Statements_of_Income_and_Expen

Statements of Income and Expenses (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
INVESTMENT INCOME
Interest income	$221		$1,107
EXPENSES
Incentive fees	106,486
Ongoing placement agent fees	68,667
Administrative fees	54,933
Management fees	51,500		57,026
Brokerage fees			198,386
Total Expenses	281,586		255,412
NET INVESTMENT LOSS	-281,365		-254,305
Trading profit (loss) on investments:
Total Trading Results	885,009		225,441
NET INCOME (LOSS)	603,644		-28,864
NET INCOME (LOSS) ALLOCATION
Limited Partners	597,114		-28,643
General Partner	6,530		-221
NET INCOME (LOSS) PER UNIT
Limited Partners	$0.38	[1]	$0	[1],[2]
General Partner	$0.38	[1]	$0	[1],[2]
WEIGHTED AVERAGE NUMBER OF UNITS OUTSTANDING	1,595,308.06		2,348,880.57
KR Master Fund [Member]
Trading profit (loss) on investments:
Net realized gain (loss) allocated			-240,940
Net change in unrealized appreciation (depreciation) allocated			422,948
Cambridge Master Fund [Member]
INVESTMENT INCOME
Interest income	761		2,977
EXPENSES
Total Expenses	28,352		66,437
NET INVESTMENT LOSS	17,606		44,946
Trading profit (loss) on investments:
Net realized gain (loss) allocated	1,789,857		-104,886
Net change in unrealized appreciation (depreciation) allocated	-904,848		148,319
Total Trading Results	2,512,143		156,075
NET INCOME (LOSS)	$2,494,537		$111,129
[1]	Represents the change in net asset value per Unit during the period.
[2]	Value less than or equal to zero.

Statements_of_Changes_in_Partn

Statements of Changes in Partners' Capital (USD $)	Total	Limited Partners [Member]	General Partner [Member]
Balance at Dec. 31, 2013	$17,969,072	$17,703,845	$265,227
Balance (in units) at Dec. 31, 2013	2,430,680.68
Net Income (Loss)	-28,864	-28,643	-221
Redemptions	-1,961,552	-1,961,552
Redemptions (in units)	-267,443.05
Balance at Mar. 31, 2014	15,978,656	15,713,650	265,006
Balance (in units) at Mar. 31, 2014	2,163,237.64
Balance at Dec. 31, 2014	13,769,331	13,623,087	146,244
Balance (in units) at Dec. 31, 2014	1,621,228.97
Net Income (Loss)	603,644	597,114	6,530
Redemptions	-705,983	-705,983
Redemptions (in units)	-80,827.66
Balance at Mar. 31, 2015	$13,666,992	$13,514,218	$152,774
Balance (in units) at Mar. 31, 2015	1,540,401.30

Organization

Organization	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Organization	1	Organization
	Morgan Stanley Smith Barney Spectrum Currency and Commodity L.P. (the “Partnership”) is a Delaware limited partnership organized in 1999 to engage primarily in the speculative trading of futures contracts, options on futures and forward contracts, and forward contracts on physical commodities and other commodity interests, including, but not limited to, foreign currencies, financial instruments, metals, energy, and agricultural products (collectively, “Futures Interests”) (refer to Note 6. Financial Instruments through the Partnership’s Investment in Affiliated Master Funds). The Partnership is one of the Morgan Stanley Spectrum series of funds, comprised of the Partnership, Morgan Stanley Smith Barney Spectrum Technical L.P., Morgan Stanley Smith Barney Spectrum Select L.P. and Morgan Stanley Smith Barney Spectrum Strategic L.P.
	Ceres Managed Futures LLC, a Delaware limited liability company, acts as the general partner (“Ceres” or the “General Partner”) and commodity pool operator for the Partnership. Ceres is a wholly-owned subsidiary of Morgan Stanley Smith Barney Holdings LLC (“MSSBH”). MSSBH is wholly-owned indirectly by Morgan Stanley. Morgan Stanley Smith Barney LLC is doing business as Morgan Stanley Wealth Management (“Morgan Stanley Wealth Management”). Morgan Stanley Wealth Management is a principal subsidiary of MSSBH.

Basis_of_Presentation_and_Summ

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	2	Basis of Presentation and Summary of Significant Accounting Policies
	The accompanying financial statements and accompanying notes are unaudited but, in the opinion of the General Partner, include all adjustments, consisting only of normal recurring adjustments, necessary for a fair presentation of the Partnership’s financial condition at March 31, 2015 and December 31, 2014 and the results of its operations and changes in partners’ capital for the three months ended March 31, 2015 and 2014. These financial statements present the results of interim periods and do not include all of the disclosures normally provided in annual financial statements. These financial statements should be read together with the financial statements and notes included in the Partnership’s December 31, 2014, Annual Report on Form 10-K (the “Form 10-K”) filed with the Securities and Exchange Commission (the “SEC”) for the year ended December 31, 2014. The December 31, 2014 information has been derived from the audited financial statements as of and for the year ended December 31, 2014.
	Use of Estimates: The preparation of financial statements and accompanying notes in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires the General Partner to make estimates and assumptions that affect the reported amounts of assets and liabilities, income and expenses, and related disclosures of contingent assets and liabilities in the financial statements and accompanying notes. As a result, actual results could differ from these estimates.
	Partnership’s Investments: The Partnership carries its affiliated investment in Cambridge Master Fund (the “Master Fund”) at fair value based on the fund’s net asset value as calculated by the fund.
	Master Fund’s Investments: The fair value of exchange-traded futures, options and forward contracts is determined by the various futures exchanges, and reflects the settlement price for each contract as of the close of business on the last business day of the reporting period. The fair value of foreign currency forward contracts is extrapolated on a forward basis from the spot prices quoted as of approximately 3:00 P.M. (E.T.) on the last business day of the reporting period from various exchanges. The fair value of non-exchange-traded foreign currency option contracts is calculated by applying an industry standard model application for options valuation of foreign currency options, using as input the spot prices, interest rates, and option implied volatilities quoted as of approximately 3:00 P.M. (E.T.) on the last business day of the reporting period.
	Investment Company Status: The Partnership adopted Accounting Standards Update (“ASU”) 2013-08, “Financial Services — Investment Companies (Topic 946): Amendments to the Scope, Measurement and Disclosure Requirements” and based on management’s assessment, the Partnership has been deemed to be an investment company since inception.
	Income Taxes: Income taxes have not been provided as each partner is individually liable for the taxes, if any, on its share of the Partnership’s income and expenses. Management has concluded that no provision for income tax is required in the Partnership’s financial statements. The Partnership files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The 2011 through 2014 tax years remain subject to examination by U.S. federal and most state tax authorities. Management does not believe that there are any uncertain tax positions that require recognition of a tax liability.
	Net Income (Loss) per Unit: Net income (loss) per unit of limited partnership interest (“Unit(s)”) is calculated in accordance with investment company guidance. See Note 3. Financial Highlights.
	Recent Accounting Pronouncements: In May 2015, the Financial Accounting Standards Board issued ASU 2015-07 “Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)” which relates to disclosures for investments that calculate net asset value per share (potentially funds of fund structures). The ASU requires investments for which the practical expedient is used to measure fair value at net asset value be removed from the fair value hierarchy. Instead, an entity is required to include those investments as a reconciling line item so that the total fair value amount of investments in the disclosure is consistent with the amount on the balance sheet. Further, the ASU requires entities to provide the disclosures in Accounting Standards Codification 820-10-50-6A only for investments for which they elect to use the net asset value practical expedient to determine fair value. The standard is effective for public business entities for fiscal years beginning after December 15, 2015, early adoption is permitted. Management is currently evaluating the impact that the new pronouncement would have on the Partnership’s financial statements.
	There have been no material changes with respect to the Partnership’s critical accounting policies as reported in the Partnership’s Annual Report on Form 10-K for the year ended December 31, 2014.

Investments_in_Affiliated_Mast

Investments in Affiliated Master Fund	3 Months Ended
	Mar. 31, 2015
Schedule of Investments [Abstract]
Investments in Affiliated Master Fund	3	Investments in Affiliated Master Fund
	The clearing commodity broker for the Cambridge Master Fund, and indirectly the Partnership, is Morgan Stanley & Co. LLC (“MS&Co.”). MS&Co. also acts as the counterparty on all trading of foreign currency forward contracts. Morgan Stanley Capital Group Inc. (“MSCG”) acts as the counterparty on all trading of options on foreign currency forward contracts for the Cambridge Master Fund. MS&Co. and MSCG are wholly-owned subsidiaries of Morgan Stanley. The trading advisor to the Partnership is The Cambridge Strategy (Assets Management) Limited (“Cambridge” or the “Trading Advisor”).
	On November 1, 2012, the Partnership allocated a portion of its assets to Cambridge for trading through investment in the Cambridge Master Fund L.P. (“Cambridge Master Fund”), a limited partnership organized under the partnership laws of the State of Delaware. Cambridge Master Fund was formed to permit accounts managed now and in the future by Cambridge using Cambridge Asian Markets Alpha Programme and, from October 1, 2013, Cambridge Emerging Markets Alpha Programme, to invest together in one trading vehicle. The General Partner is also the general partner of Cambridge Master Fund. Individual and pooled accounts currently managed by Cambridge, including the Partnership, are permitted to be limited partners of Cambridge Master Fund. The General Partner and Cambridge believe that trading through this structure should provide efficiency and economy in the trading process.
	As of March 31, 2015 and December 31, 2014, the Partnership owned approximately 34.88% and 31.51% of Cambridge Master Fund, respectively. It is the Partnership’s intention to continue to invest in Cambridge Master Fund. The performance of the Partnership is directly affected by the performance of Cambridge Master Fund, and prior to termination on December 31, 2014, KR Master Fund.
	Effective December 31, 2014, the Partnership fully redeemed its investment from KR Master Fund L.P. (“KR Master Fund”). In addition, Krom River Investment Management (Cayman) Limited and Krom River Trading AG (together, and each separately, “Krom River”) no longer act as commodity trading advisor to the Partnership. Effective on or about January 1, 2015, the Partnership reallocated the assets allocated to Krom River to the existing commodity trading advisor in the Partnership.
	Cambridge Master Fund’s Statements of Financial Condition and Condensed Schedules of Investments as of March 31, 2015 and December 31, 2014, and Statements of Income and Expenses and Changes in Partners’ Capital for the three months ended March 31, 2015 and 2014 are presented below:
	Cambridge Master Fund L.P.
	Statements of Financial Condition
		March 31,			December 31,
		2015			2014
		(Unaudited)
		$			$
	Assets:
	Equity in trading account:
	Cash		22,530,016			26,503,935
	Cash margin		17,740,912			9,794,931
	Net unrealized appreciation on open forward contracts		148,699			2,739,853
	Total Trading Equity		40,419,627			39,038,719
	Expense Reimbursement		3,430			7,922
	Total assets		40,423,057			39,046,641
	Liabilities and Partners’ Capital:
	Accrued expenses:
	Professional fees		63,431			48,456
	Total liabilities		63,431			48,456
	Partners’ Capital:
	General Partner		—			—
	Limited Partners		40,359,626			38,998,185
	Total liabilities and Partners’ Capital		40,423,057			39,046,641
	Cambridge Master Fund L.P.
	Condensed Schedules of Investments
	March 31, 2015 (Unaudited)
		Notional			Fair Value			% of Partners’
								Capital
		$			$			%
	Unrealized Appreciation on Open Forward Contracts
	Currencies		660,059,999			6,499,773			16.11
	Total unrealized appreciation on open forward contracts					6,499,773			16.11
	Unrealized Depreciation on Open Forward Contracts
	Currencies		653,448,702			(6,351,074	)		(15.74	)
	Total unrealized depreciation on open forward contracts					(6,351,074	)		(15.74	)
	Net fair value					148,699			0.37
	December 31, 2014
		Notional			Fair Value			% of Partners’
								Capital
		$			$			%
	Unrealized Appreciation on Open Forward Contracts
	Currencies		391,686,862			5,969,177			15.31
	Total unrealized appreciation on open forward contracts					5,969,177			15.31
	Unrealized Depreciation on Open Forward Contracts
	Currencies		284,639,685			(3,229,324	)		(8.28	)
	Total unrealized depreciation on open forward contracts					(3,229,324	)		(8.28	)
	Net fair value					2,739,853			7.03
	Cambridge Master Fund L.P.
	Statements of Income and Expenses
	for the Three Months ended March 31, 2015 and 2014
	(Unaudited)
		For the Three Months ended March 31,
		2015			2014
		$			$
	Investment Income:
	Interest income		761			2,977
	Expenses:
	Clearing fees		3,323			42,791
	Professional fees		25,029			23,646
Total expenses		28,352			66,437
Expense reimbursements		(9,985	)		(18,514	)
Net expenses		18,367			47,923
Net investment income (loss)		(17,606	)		(44,946	)
Trading Results:
Net gains (losses) on trading of commodity interests:
Net realized gains (losses) on closed contracts		5,103,297			(376,472	)
Change in net unrealized gains (losses) on open contracts		(2,591,154	)		532,547
Total trading results		2,512,143			156,075
NET INCOME		2,494,537			111,129
Cambridge Master Fund L.P.
Statements of Changes in Partners’ Capital
for the Three Months ended March 31, 2015 and 2014
(Unaudited)
	Partners’
	Capital
	$
Partners’ Capital at December 31, 2013		37,521,384
Net income		111,129
Subscriptions		3,000,000
Redemptions		(557,971	)
Distribution of interest income to feeder funds		(2,977	)
Partners’ Capital at March 31, 2014		40,071,565
Partners’ Capital at December 31, 2014		38,998,185
Net income		2,494,537
Subscriptions		1,636,080
Redemptions		(2,768,415	)
Distribution of interest income to feeder funds		(761	)
Partners’ Capital at March 31, 2015		40,359,626

Financial_Highlights

Financial Highlights	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Highlights	4		Financial Highlights
	Financial highlights of the limited partner class for the Partnership and Cambridge Master Fund for the three months ended March 31, 2015 and 2014 were as follows:
	Financial Highlights of the Partnership:		For the Three Months Ended March 31,
			2015			2014
	Per Unit Operating Performance:
	Net asset value, January 1:		$	8.49		$	7.39
	Interest Income			—	(2)		—	(2)
	Expenses			(0.18	)		(0.11	)
	Realized/Unrealized Gains			0.56			0.11
	Net Income (Loss)			0.38			—	(2)
	Net asset value, March 31:		$	8.87		$	7.39
	Ratios to average net assets:
	Net Investment Loss (1)			(6.0	)%		(6.2	)%
	Expenses before Incentive Fees (1)			5.2	%		6.2	%
	Expenses after Incentive Fees (1)			6	%		6.2	%
	Total return before incentive fees			5.3	%		0	%
	Total return after incentive fees			4.5	%		0	%
	(1)	Annualized (except for incentive fees, if applicable).
	(2)	Amount less than $0.005 per Unit.
	The above ratios and total return may vary for individual investors based on the timing of capital transactions during the period. Additionally, these ratios are calculated for the limited partner class using the limited partners’ share of income, expenses and average net assets, and includes the income and expenses allocated from the Master Fund.
	Financial Highlights of Cambridge Master Fund:
	Ratios to average net assets for the three months ended March 31, 2015 and 2014 were as follows:
			For the Three Months Ended March 31,
			2015			2014
	Ratios to average net assets:
	Net investment income (loss)*			(0.2	)%		(0.5	)%
	Operating expenses			0.2	%		0.5	%
	Total return			6.5	%		0.3	%
	*	Interest income less total expenses.
	The above ratios and the return may vary for individual investors based on the timing of capital transactions during the period. Additionally, these ratios are calculated for the limited partner class using the limited partners’ share of income, expenses and average net assets.

Related_Party_Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	5	Related Party Transactions
	The Master Fund’s cash is on deposit in commodity brokerage accounts with Morgan Stanley. MS&Co. pays the Master Fund’s interest income on 100% of the average daily equity maintained in the Master Fund’s account during each month at a rate equal to 80% of the monthly average of the 4-week U.S. Treasury bill discount rate. MS&Co. retains any interest earned in excess of the interest paid to the Master Fund. For purposes of such interest payments, net assets do not include monies due to the Master Fund on Futures Interests that have not been received. The Partnership pays a general partner administrative fee to the General Partner and an ongoing placement agent fee to Morgan Stanley Wealth Management. Prior to October 2014, a flat rate brokerage fee was payable to MS&Co. The General Partner pays or reimburses the Partnership for all brokerage fees and costs charged or incurred by MS&Co., the General Partner and/or its affiliates or any other entity acting as a commodity broker for the Partnership. For the three months ended March 31, 2015, the fees were $30,875.

Financial_Instruments_through_

Financial Instruments through the Partnership's Investment in Affiliated Master Funds	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Financial Instruments through the Partnership's Investment in Affiliated Master Funds	6	Financial Instruments through the Partnership’s Investment in Affiliated Master Funds
	Cambridge Master Fund, and indirectly the Partnership, trades Futures Interests. Futures and forwards represent contracts for delayed delivery of an instrument at a specified date and price. Futures Interests are open commitments until the settlement date, at which time they are realized. They are valued at fair value, generally on a daily basis, and the unrealized gains and losses on open contracts (the difference between contract trade price and market price) are reported in the Statements of Financial Condition as a net unrealized gain or loss on open contracts. The resulting net change in unrealized gains and losses is reflected in the “Net change in unrealized” trading profit (loss) and “Net change in unrealized appreciation (depreciation) allocated from Cambridge Master Fund” on open contracts from one period to the next on the Statements of Income and Expenses. The Cambridge Master Fund’s contracts are accounted for on a trade-date basis. Risk arises from changes in the value of these contracts and the potential inability of counterparties to perform under the terms of the contracts. There are numerous factors which may significantly influence the fair value of these contracts, including interest rate volatility.
	The fair value of an exchange-traded contract is based on the settlement price quoted by the exchange on the day with respect to which fair value is being determined. If an exchange-traded contract could not have been liquidated on such day due to the operation of daily limits or other rules of the exchange, the settlement price will be equal to the settlement price on the first subsequent day on which the contract could be liquidated.
	The futures, forwards and options traded by the Partnership involve varying degrees of related market risk. Market risk is often dependent upon changes in the level or volatility of interest rates, exchange rates, and prices of financial instruments and commodities, factors that result in frequent changes in the fair value of the Partnership’s open positions, and consequently in its earnings, whether realized or unrealized, and cash flow. Gains and losses on open positions of exchange-traded futures, exchange-traded forward, and exchange-traded futures-styled options contracts are settled daily through variation margin. Gains and losses on off-exchange-traded forward currency contracts are settled upon termination of the contract. Gains and losses on off-exchange-traded forward currency options contracts are settled on an agreed-upon settlement date.

Derivatives_and_Hedging

Derivatives and Hedging	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging	7		Derivatives and Hedging
	The Partnership’s objective, through its investment in the Master Fund, is to profit from speculative trading in Futures Interests. Therefore, the Trading Advisor for the Partnership will take speculative positions in Futures Interests where it feels the best profit opportunities exist for its trading strategy. As such, the average number of contracts outstanding in absolute quantities (the total of the open long and open short positions) has been presented as a part of the volume disclosure, as position direction is not an indicative factor in such volume disclosures. With regard to foreign currency forward trades, each notional quantity amount has been converted to an equivalent contract based upon an industry convention.
	The monthly average notional values of currency forward contracts traded during the three months ended March 31, 2015 and 2014 were $1,509,891,555 and $1,761,912,299, respectively.
	The following tables summarize the gross and net amounts recognized relating to assets and liabilities of Cambridge Master Fund’s derivative instruments and transactions eligible for offset subject to master netting agreements or similar agreements as of March 31, 2015 and December 31, 2014.
	Offsetting of Derivative Assets and Liabilities as of March 31, 2015:
											Gross amounts not offset in the
											Statements of Financial Condition
			Gross Amounts			Gross Amounts			Net Amounts		Financial		Cash Collateral		Net Amount
			Recognized			Offset in the			Presented in the		Instruments		Received/Pledged*
						Statements of			Statements of
						Financial			Financial
						Condition			Condition
			$			$			$		$		$		$
	Assets
	Forwards			6,499,773			(6,351,074	)		148,699		—		—		148,699
	Total Assets			6,499,773			(6,351,074	)		148,699		—		—		148,699
	Liabilities
	Forwards			(6,351,074	)		6,351,074			—		—		—		—
	Total Liabilities			(6,351,074	)		6,351,074			—		—		—		—
	Net unrealized appreciation on open forwards contracts									148,699						148,699	*
	Offsetting of Derivative Assets and Liabilities as of December 31, 2014:
											Gross amounts not offset in the
											Statements of Financial Condition
			Gross Amounts			Gross Amounts			Net Amounts		Financial		Cash Collateral		Net Amount
			Recognized			Offset in the			Presented in the		Instruments		Received/Pledged*
						Statements of			Statements of
						Financial			Financial
						Condition			Condition
			$			$			$		$		$		$
	Assets
	Forwards			5,969,177			(3,229,324	)		2,739,853		—		—		2,739,853
	Total Assets			5,969,177			(3,229,324	)		2,739,853		—		—		2,739,853
	Liabilities
	Forwards			(3,229,324	)		3,229,324			—		—		—		—
	Total Liabilities			(3,229,324	)		3,229,324			—		—		—		—
	Net unrealized appreciation on open forwards contracts									2,739,853						2,739,853	*
	*	In the event of default by Cambridge Master Fund, MS&Co., the sole counterparty to the Cambridge Master Fund’s derivative contracts, has the right to offset the Cambridge Master Fund’s obligation with the cash held by Cambridge Master Fund, thereby minimizing the counterparty’s risk of loss. There is no collateral posted by MS&Co. and as such, in the event of default by MS&Co., Cambridge Master Fund is exposed to the amount shown on the Statements of Financial Condition.
	The following tables indicate the gross fair values of derivative instruments of forward contracts as separate assets and liabilities as of March 31, 2015 and December 31, 2014.
			March 31,
			2015
			$
	Assets
	Forward Contracts
	Currencies			6,499,773
	Total unrealized appreciation on open forward contracts			6,499,773
	Liabilities
	Forward Contracts
	Currencies			(6,351,074	)
	Total unrealized depreciation on open forward contracts			(6,351,074	)
	Net unrealized appreciation on open forward contracts			148,699	*
	*	This amount is included in “Net unrealized appreciation on open forward contracts” on the Statements of Financial Condition.
			December 31,
			2014
			$
	Assets
	Forward Contracts
	Currencies			5,969,177
	Total unrealized appreciation on open forward contracts			5,969,177
	Liabilities
	Forward Contracts
	Currencies			(3,229,324	)
	Total unrealized depreciation on open forward contracts			(3,229,324	)
	Net unrealized appreciation on open forward contracts			2,739,853	*
	*	This amount is included in “Net unrealized appreciation on open forward contracts” on the Statements of Financial Condition.
The following tables indicate the trading gains and losses, by market sector, on derivative instruments for the three months ended March 31, 2015 and 2014.
		Three Months
Sector		March 31,			March 31,
		2015			2014
		$			$
Currencies			2,512,143			156,075
Total			2,512,143	**		156,075	**
**	This amount is included in “Total trading results” on the Statement of Income and Expenses.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	8	Fair Value Measurements
	Cambridge Master Fund’s Investments:
	All commodity interests of the Cambridge Master Fund, including derivative financial instruments and derivative commodity instruments, are held for trading purposes. The commodity interests are recorded on trade date and open contracts are recorded at fair value (as described below) at the measurement date. Investments in commodity interests denominated in foreign currencies are translated into U.S. dollars at the exchange rates prevailing at the measurement date. Gains or losses are realized when contracts are liquidated. Unrealized gains or losses on open contracts are included as a component of equity in trading account on the Statements of Financial Condition. Net realized gains or losses and any change in net unrealized gains or losses are included in the Statements of Income and Expenses.
	Cambridge Master Fund’s Fair Value Measurements:
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date under current market conditions. The fair value hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to fair values derived from unobservable inputs (Level 3). The level in the fair value hierarchy within which the fair value measurement in its entirety falls shall be determined based on the lowest level input that is significant to the fair value measurement in its entirety.
	Cambridge Master Funds considers prices for exchange-traded commodity futures, forwards, swaps and option contracts to be based on unadjusted quoted prices in active markets for identical assets and liabilities (Level 1). The values of non-exchange-traded forwards, swaps and certain options contracts for which market quotations are not readily available are priced by broker-dealers that derive fair values for those assets and liabilities from observable inputs (Level 2). As of and for the quarter ended March 31, 2015 and for the year ended December 31, 2014, Cambridge Master Fund did not hold any derivative instruments that were based on unadjusted quoted prices in active markets for identical assets and liabilities (Level 1) or that were priced at fair value using unobservable inputs through the application of the General Partner’s assumptions and internal valuation pricing models (Level 3). Transfers between levels are recognized at the end of the reporting period. During the period from January 1, 2015 to March 31, 2015, and for the twelve months ended December 31, 2014, there were no transfers of assets or liabilities between Level 1 and Level 2.
	March 31, 2015	Level 1		Level 2			Level 3		Total
		$		$			$		$
	Assets
	Forwards		—		6,499,773			—		6,499,773
	Total Assets		—		6,499,773			—		6,499,773
	Liabilities
	Forwards		—		(6,351,074	)		—		(6,351,074	)
	Total Liabilities		—		(6,351,074	)		—		(6,351,074	)
	Net fair value		—		148,699			—		148,699
		Level 1		Level 2			Level 3		Total
	31-Dec-14
		$		$			$		$
	Assets
	Forwards		—		5,969,177			—		5,969,177
	Total Assets		—		5,969,177			—		5,969,177
	Liabilities
	Forwards		—		3,229,324			—		3,229,324
	Total Liabilities		—		3,229,324			—		3,229,324
	Net fair value		—		2,739,853			—		2,739,853

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	9	Subsequent Events
	Management of the Partnership performed its evaluation of subsequent events through the date of filing, and has determined that there were no subsequent events requiring adjustment of or disclosure in the financial statements.

Basis_of_Presentation_and_Summ1

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates: The preparation of financial statements and accompanying notes in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires the General Partner to make estimates and assumptions that affect the reported amounts of assets and liabilities, income and expenses, and related disclosures of contingent assets and liabilities in the financial statements and accompanying notes. As a result, actual results could differ from these estimates.
Partnership's Investments	Partnership’s Investments: The Partnership carries its affiliated investment in Cambridge Master Fund (the “Master Fund”) at fair value based on the fund’s net asset value as calculated by the fund.
Master Fund's Investments	Master Fund’s Investments: The fair value of exchange-traded futures, options and forward contracts is determined by the various futures exchanges, and reflects the settlement price for each contract as of the close of business on the last business day of the reporting period. The fair value of foreign currency forward contracts is extrapolated on a forward basis from the spot prices quoted as of approximately 3:00 P.M. (E.T.) on the last business day of the reporting period from various exchanges. The fair value of non-exchange-traded foreign currency option contracts is calculated by applying an industry standard model application for options valuation of foreign currency options, using as input the spot prices, interest rates, and option implied volatilities quoted as of approximately 3:00 P.M. (E.T.) on the last business day of the reporting period.
Investment Company Status	Investment Company Status: The Partnership adopted Accounting Standards Update (“ASU”) 2013-08, “Financial Services — Investment Companies (Topic 946): Amendments to the Scope, Measurement and Disclosure Requirements” and based on management’s assessment, the Partnership has been deemed to be an investment company since inception.
Income Taxes	Income Taxes: Income taxes have not been provided as each partner is individually liable for the taxes, if any, on its share of the Partnership’s income and expenses. Management has concluded that no provision for income tax is required in the Partnership’s financial statements. The Partnership files U.S. federal and various state and local tax returns. No income tax returns are currently under examination. The 2011 through 2014 tax years remain subject to examination by U.S. federal and most state tax authorities. Management does not believe that there are any uncertain tax positions that require recognition of a tax liability.
Net Income (Loss) per Unit	Net Income (Loss) per Unit: Net income (loss) per unit of limited partnership interest (“Unit(s)”) is calculated in accordance with investment company guidance. See Note 3. Financial Highlights.
Recent Accounting Pronouncements	Recent Accounting Pronouncements: In May 2015, the Financial Accounting Standards Board issued ASU 2015-07 “Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)” which relates to disclosures for investments that calculate net asset value per share (potentially funds of fund structures). The ASU requires investments for which the practical expedient is used to measure fair value at net asset value be removed from the fair value hierarchy. Instead, an entity is required to include those investments as a reconciling line item so that the total fair value amount of investments in the disclosure is consistent with the amount on the balance sheet. Further, the ASU requires entities to provide the disclosures in Accounting Standards Codification 820-10-50-6A only for investments for which they elect to use the net asset value practical expedient to determine fair value. The standard is effective for public business entities for fiscal years beginning after December 15, 2015, early adoption is permitted. Management is currently evaluating the impact that the new pronouncement would have on the Partnership’s financial statements.
	There have been no material changes with respect to the Partnership’s critical accounting policies as reported in the Partnership’s Annual Report on Form 10-K for the year ended December 31, 2014.

Investments_in_Affiliated_Mast1

Investments in Affiliated Master Fund (Tables) (Cambridge Master Fund [Member])	3 Months Ended
	Mar. 31, 2015
Cambridge Master Fund [Member]
Statements of Financial Condition	Cambridge Master Fund L.P.
	Statements of Financial Condition
		March 31,			December 31,
		2015			2014
		(Unaudited)
		$			$
	Assets:
	Equity in trading account:
	Cash		22,530,016			26,503,935
	Cash margin		17,740,912			9,794,931
	Net unrealized appreciation on open forward contracts		148,699			2,739,853
	Total Trading Equity		40,419,627			39,038,719
	Expense Reimbursement		3,430			7,922
	Total assets		40,423,057			39,046,641
	Liabilities and Partners’ Capital:
	Accrued expenses:
	Professional fees		63,431			48,456
	Total liabilities		63,431			48,456
	Partners’ Capital:
	General Partner		—			—
	Limited Partners		40,359,626			38,998,185
	Total liabilities and Partners’ Capital		40,423,057			39,046,641
Condensed Schedules of Investments	Cambridge Master Fund L.P.
	Condensed Schedules of Investments
	March 31, 2015 (Unaudited)
		Notional			Fair Value			% of Partners’
								Capital
		$			$			%
	Unrealized Appreciation on Open Forward Contracts
	Currencies		660,059,999			6,499,773			16.11
	Total unrealized appreciation on open forward contracts					6,499,773			16.11
	Unrealized Depreciation on Open Forward Contracts
	Currencies		653,448,702			(6,351,074	)		(15.74	)
	Total unrealized depreciation on open forward contracts					(6,351,074	)		(15.74	)
	Net fair value					148,699			0.37
	December 31, 2014
		Notional			Fair Value			% of Partners’
								Capital
		$			$			%
	Unrealized Appreciation on Open Forward Contracts
	Currencies		391,686,862			5,969,177			15.31
	Total unrealized appreciation on open forward contracts					5,969,177			15.31
	Unrealized Depreciation on Open Forward Contracts
	Currencies		284,639,685			(3,229,324	)		(8.28	)
	Total unrealized depreciation on open forward contracts					(3,229,324	)		(8.28	)
	Net fair value					2,739,853			7.03
Statements of Income and Expenses	Cambridge Master Fund L.P.
	Statements of Income and Expenses
	for the Three Months ended March 31, 2015 and 2014
	(Unaudited)
		For the Three Months ended March 31,
		2015			2014
		$			$
	Investment Income:
	Interest income		761			2,977
	Expenses:
	Clearing fees		3,323			42,791
	Professional fees		25,029			23,646
	Total expenses		28,352			66,437
	Expense reimbursements		(9,985	)		(18,514	)
	Net expenses		18,367			47,923
	Net investment income (loss)		(17,606	)		(44,946	)
	Trading Results:
	Net gains (losses) on trading of commodity interests:
	Net realized gains (losses) on closed contracts		5,103,297			(376,472	)
	Change in net unrealized gains (losses) on open contracts		(2,591,154	)		532,547
	Total trading results		2,512,143			156,075
	NET INCOME		2,494,537			111,129
Statements of Changes in Partners' Capital	Cambridge Master Fund L.P.
	Statements of Changes in Partners’ Capital
	for the Three Months ended March 31, 2015 and 2014
	(Unaudited)
		Partners’
		Capital
		$
	Partners’ Capital at December 31, 2013		37,521,384
	Net income		111,129
	Subscriptions		3,000,000
	Redemptions		(557,971	)
	Distribution of interest income to feeder funds		(2,977	)
	Partners’ Capital at March 31, 2014		40,071,565
	Partners’ Capital at December 31, 2014		38,998,185
	Net income		2,494,537
	Subscriptions		1,636,080
	Redemptions		(2,768,415	)
	Distribution of interest income to feeder funds		(761	)
	Partners’ Capital at March 31, 2015		40,359,626

Financial_Highlights_Tables

Financial Highlights (Tables)	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Highlights for Limited Partner Class	Financial highlights of the limited partner class for the Partnership and Cambridge Master Fund for the three months ended March 31, 2015 and 2014 were as follows:
	Financial Highlights of the Partnership:		For the Three Months Ended March 31,
			2015			2014
	Per Unit Operating Performance:
	Net asset value, January 1:		$	8.49		$	7.39
	Interest Income			—	(2)		—	(2)
	Expenses			(0.18	)		(0.11	)
	Realized/Unrealized Gains			0.56			0.11
	Net Income (Loss)			0.38			—	(2)
	Net asset value, March 31:		$	8.87		$	7.39
	Ratios to average net assets:
	Net Investment Loss (1)			(6.0	)%		(6.2	)%
	Expenses before Incentive Fees (1)			5.2	%		6.2	%
	Expenses after Incentive Fees (1)			6	%		6.2	%
	Total return before incentive fees			5.3	%		0	%
	Total return after incentive fees			4.5	%		0	%
	(1)	Annualized (except for incentive fees, if applicable).
	(2)	Amount less than $0.005 per Unit.
	The above ratios and total return may vary for individual investors based on the timing of capital transactions during the period. Additionally, these ratios are calculated for the limited partner class using the limited partners’ share of income, expenses and average net assets, and includes the income and expenses allocated from the Master Fund.
	Financial Highlights of Cambridge Master Fund:
	Ratios to average net assets for the three months ended March 31, 2015 and 2014 were as follows:
			For the Three Months Ended March 31,
			2015			2014
	Ratios to average net assets:
	Net investment income (loss)*			(0.2	)%		(0.5	)%
	Operating expenses			0.2	%		0.5	%
	Total return			6.5	%		0.3	%
	*	Interest income less total expenses.

Derivatives_and_Hedging_Tables

Derivatives and Hedging (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Offsetting Of Derivative Assets And Liabilities	Offsetting of Derivative Assets and Liabilities as of March 31, 2015:
											Gross amounts not offset in the
											Statements of Financial Condition
			Gross Amounts			Gross Amounts			Net Amounts		Financial		Cash Collateral		Net Amount
			Recognized			Offset in the			Presented in the		Instruments		Received/Pledged*
						Statements of			Statements of
						Financial			Financial
						Condition			Condition
			$			$			$		$		$		$
	Assets
	Forwards			6,499,773			(6,351,074	)		148,699		—		—		148,699
	Total Assets			6,499,773			(6,351,074	)		148,699		—		—		148,699
	Liabilities
	Forwards			(6,351,074	)		6,351,074			—		—		—		—
	Total Liabilities			(6,351,074	)		6,351,074			—		—		—		—
	Net unrealized appreciation on open forwards contracts									148,699						148,699	*
	Offsetting of Derivative Assets and Liabilities as of December 31, 2014:
											Gross amounts not offset in the
											Statements of Financial Condition
			Gross Amounts			Gross Amounts			Net Amounts		Financial		Cash Collateral		Net Amount
			Recognized			Offset in the			Presented in the		Instruments		Received/Pledged*
						Statements of			Statements of
						Financial			Financial
						Condition			Condition
			$			$			$		$		$		$
	Assets
	Forwards			5,969,177			(3,229,324	)		2,739,853		—		—		2,739,853
	Total Assets			5,969,177			(3,229,324	)		2,739,853		—		—		2,739,853
	Liabilities
	Forwards			(3,229,324	)		3,229,324			—		—		—		—
	Total Liabilities			(3,229,324	)		3,229,324			—		—		—		—
	Net unrealized appreciation on open forwards contracts									2,739,853						2,739,853	*
	*	In the event of default by Cambridge Master Fund, MS&Co., the sole counterparty to the Cambridge Master Fund’s derivative contracts, has the right to offset the Cambridge Master Fund’s obligation with the cash held by Cambridge Master Fund, thereby minimizing the counterparty’s risk of loss. There is no collateral posted by MS&Co. and as such, in the event of default by MS&Co., Cambridge Master Fund is exposed to the amount shown on the Statements of Financial Condition.
Summary of Gross Fair Values of Derivative Instruments	The following tables indicate the gross fair values of derivative instruments of forward contracts as separate assets and liabilities as of March 31, 2015 and December 31, 2014.
			March 31,
			2015
			$
	Assets
	Forward Contracts
	Currencies			6,499,773
	Total unrealized appreciation on open forward contracts			6,499,773
	Liabilities
	Forward Contracts
	Currencies			(6,351,074	)
	Total unrealized depreciation on open forward contracts			(6,351,074	)
	Net unrealized appreciation on open forward contracts			148,699	*
	*	This amount is included in “Net unrealized appreciation on open forward contracts” on the Statements of Financial Condition.
			December 31,
			2014
			$
	Assets
	Forward Contracts
	Currencies			5,969,177
	Total unrealized appreciation on open forward contracts			5,969,177
	Liabilities
	Forward Contracts
	Currencies			(3,229,324	)
	Total unrealized depreciation on open forward contracts			(3,229,324	)
	Net unrealized appreciation on open forward contracts			2,739,853	*
	*	This amount is included in “Net unrealized appreciation on open forward contracts” on the Statements of Financial Condition.
Summary of Trading Gains and Losses, by Market Sector, on Derivatives Instruments	The following tables indicate the trading gains and losses, by market sector, on derivative instruments for the three months ended March 31, 2015 and 2014.
			Three Months
	Sector		March 31,			March 31,
			2015			2014
			$			$
	Currencies			2,512,143			156,075
	Total			2,512,143	**		156,075	**
	**	This amount is included in “Total trading results” on the Statement of Income and Expenses.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables) (Cambridge Master Fund [Member])	3 Months Ended
	Mar. 31, 2015
Cambridge Master Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
	March 31, 2015	Level 1		Level 2			Level 3		Total
		$		$			$		$
	Assets
	Forwards		—		6,499,773			—		6,499,773
	Total Assets		—		6,499,773			—		6,499,773
	Liabilities
	Forwards		—		(6,351,074	)		—		(6,351,074	)
	Total Liabilities		—		(6,351,074	)		—		(6,351,074	)
	Net fair value		—		148,699			—		148,699
		Level 1		Level 2			Level 3		Total
	31-Dec-14
		$		$			$		$
	Assets
	Forwards		—		5,969,177			—		5,969,177
	Total Assets		—		5,969,177			—		5,969,177
	Liabilities
	Forwards		—		3,229,324			—		3,229,324
	Total Liabilities		—		3,229,324			—		3,229,324
	Net fair value		—		2,739,853			—		2,739,853

Basis_of_Presentation_and_Summ2

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 24, 2015
Accounting Policies [Abstract]
Provision for income tax	$0

Investments_in_Affiliated_Mast2

Investments in Affiliated Master Fund - Additional information (Detail) (Cambridge Master Fund [Member])	Mar. 31, 2015	Mar. 31, 2014
Cambridge Master Fund [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage	34.88%	31.51%

Investments_in_Affiliated_Mast3

Investments in Affiliated Master Fund - Statements of Financial Condition (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Equity in trading account:
Net unrealized appreciation on open forward contracts	$148,699	$2,739,853
Total Assets	14,078,876	14,172,143
Accrued expenses:
Total Liabilities	411,884	402,812
Partners' Capital:
General Partner	152,774	146,244
Limited Partners	13,514,218	13,623,087
Total Liabilities and Partners' Capital	14,078,876	14,172,143
Cambridge Master Fund [Member]
Equity in trading account:
Cash	22,530,016	26,503,935
Cash margin	17,740,912	9,794,931
Net unrealized appreciation on open forward contracts	148,699	2,739,853
Total Trading Equity	40,419,627	39,038,719
Expense Reimbursement	3,430	7,922
Total Assets	40,423,057	39,046,641
Accrued expenses:
Professional fees	63,431	48,456
Total Liabilities	63,431	48,456
Partners' Capital:
General Partner	0	0
Limited Partners	40,359,626	38,998,185
Total Liabilities and Partners' Capital	$40,423,057	$39,046,641

Investments_in_Affiliated_Mast4

Investments in Affiliated Master Fund - Condensed Schedules of Investments (Detail) (Cambridge Master Fund [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Total unrealized appreciation on open forward contracts, Fair Value	$6,499,773	$5,969,177
Total unrealized depreciation on open forward contracts, Fair Value	-6,351,074	-3,229,324
Net fair value	148,699	2,739,853
Net fair value, Percentage of Partners' Capital	0.37%	7.03%
Currencies [Member]
Investment Holdings [Line Items]
Total unrealized appreciation on open forward contracts, Fair Value	6,499,773	5,969,177
Total unrealized depreciation on open forward contracts, Fair Value	-6,351,074	-3,229,324
Unrealized Appreciation on Open Forward Contracts [Member]
Investment Holdings [Line Items]
Percentage of Partners' Capital	16.11%	15.31%
Unrealized Appreciation on Open Forward Contracts [Member] | Currencies [Member]
Investment Holdings [Line Items]
Open Forward Contracts, Notional amount	660,059,999	391,686,862
Percentage of Partners' Capital	16.11%	15.31%
Unrealized Depreciation on Open Forward Contracts [Member]
Investment Holdings [Line Items]
Percentage of Partners' Capital	-15.74%	-8.28%
Unrealized Depreciation on Open Forward Contracts [Member] | Currencies [Member]
Investment Holdings [Line Items]
Open Forward Contracts, Notional amount	$653,448,702	$284,639,685
Percentage of Partners' Capital	-15.74%	-8.28%

Investments_in_Affiliated_Mast5

Investments in Affiliated Master Fund - Statements of Income and Expenses (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Investment Income:
Interest income	$221	$1,107
Expenses:
Total Expenses	281,586	255,412
Net investment income (loss)	281,365	254,305
Net gains (losses) on trading of commodity interests:
Total Trading Results	885,009	225,441
NET INCOME	603,644	-28,864
Cambridge Master Fund [Member]
Investment Income:
Interest income	761	2,977
Expenses:
Clearing fees	3,323	42,791
Professional fees	25,029	23,646
Total Expenses	28,352	66,437
Expense reimbursements	-9,985	-18,514
Net expenses	18,367	47,923
Net investment income (loss)	-17,606	-44,946
Net gains (losses) on trading of commodity interests:
Net realized gains (losses) on closed contracts	5,103,297	-376,472
Change in net unrealized gains (losses) on open contracts	-2,591,154	532,547
Total Trading Results	2,512,143	156,075
NET INCOME	$2,494,537	$111,129

Investments_in_Affiliated_Mast6

Investments in Affiliated Master Fund - Statements of Changes in Partners' Capital (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Limited Partners' Capital Account [Line Items]
Balance	$13,769,331	$17,969,072
NET INCOME	603,644	-28,864
Redemptions	-705,983	-1,961,552
Balance	13,666,992	15,978,656
Cambridge Master Fund [Member]
Limited Partners' Capital Account [Line Items]
Balance	38,998,185	37,521,384
NET INCOME	2,494,537	111,129
Subscriptions	1,636,080	3,000,000
Redemptions	-2,768,415	-557,971
Distribution of interest income to feeder funds	-761	-2,977
Balance	$40,359,626	$40,071,565

Financial_Highlights_Financial

Financial Highlights - Financial Highlights for Limited Partner Class (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Per Unit Operating Performance:
Net asset value, beginning of period	$8.49		$7.39
Expenses	($0.18)		($0.11)
Realized/Unrealized Gains	$0.56		$0.11
Net Income (Loss)	$0.38	[1]	$0	[1],[2]
Net asset value, end of period	$8.87		$7.39
Ratios to average net assets:
Net investment income (loss)	-6.00%		-6.20%
Expenses before Incentive Fees	5.20%		6.20%
Expenses after Incentive Fees	6.00%		6.20%
Total return before incentive fees	5.30%		0.00%
Total return after incentive fees	4.50%		0.00%
Cambridge Master Fund [Member]
Ratios to average net assets:
Net investment income (loss)	-0.20%		-0.50%
Operating expenses	0.20%		0.50%
Total return	6.50%		0.30%
[1]	Represents the change in net asset value per Unit during the period.
[2]	Value less than or equal to zero.

Financial_Highlights_Financial1

Financial Highlights - Financial Highlights for Limited Partner Class (Parenthetical) (Detail) (Maximum [Member], USD $)	3 Months Ended
	Mar. 31, 2014
Maximum [Member]
Financial Highlights Disclosures [Line Items]
Interest Income	$0.01

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Schedule of Other Related Party Transactions [Line Items]
Cash holdings percentage for margin requirements used in interest income calculation (in hundredths)	100.00%
Percentage of monthly average of 4-week U.S. treasury bill discount rate as rate from partnership interest income (in hundredths)	80.00%
Brokerage fees		$198,386
General Partner [Member]
Schedule of Other Related Party Transactions [Line Items]
Brokerage fees	30,875

Derivatives_and_Hedging_Additi

Derivatives and Hedging - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Average notional values of currency forward contracts	$1,509,891,555	$1,761,912,299

Derivatives_and_Hedging_Offset

Derivatives and Hedging - Offsetting Of Derivative Assets and Liabilities (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Trading Activity, Gains and Losses, Net [Line Items]
Gross Amounts Recognized, Total Assets	$6,499,773	$5,969,177
Gross Amounts Offset in the Statements of Financial Condition, Total Assets	-6,351,074	-3,229,324
Net Amounts Presented in the Statement of Financial Condition, Total Assets	148,699	2,739,853
Financial Instruments, Total Assets	0	0
Cash Collateral Received/Pledged, Total Assets	0	0
Net Amount, Assets, Total Assets	148,699	2,739,853
Gross Amounts Recognized, Total Liabilities	-6,351,074	-3,229,324
Gross Amounts Offset in the Statement of Financial Condition, Total Liabilities	6,351,074	3,229,324
Net Amounts Presented in the Statement of Financial Condition, Total Liabilities	0	0
Financial Instruments, Liabilities	0	0
Cash Collateral Received/Pledged, Liabilities	0	0
Net Amount, Liabilities	0	0
Net unrealized appreciation on open forwards contracts	148,699	2,739,853
Total net unrealized gain (loss) on open contracts, amounts not offset	148,699	2,739,853
Forward Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Gross Amounts Recognized, Total Assets	6,499,773	5,969,177
Gross Amounts Offset in the Statements of Financial Condition, Total Assets	-6,351,074	-3,229,324
Net Amounts Presented in the Statement of Financial Condition, Total Assets	148,699	2,739,853
Financial Instruments, Total Assets	0	0
Cash Collateral Received/Pledged, Total Assets	0	0
Net Amount, Assets, Total Assets	148,699	2,739,853
Gross Amounts Recognized, Total Liabilities	-6,351,074	-3,229,324
Gross Amounts Offset in the Statement of Financial Condition, Total Liabilities	6,351,074	3,229,324
Net Amounts Presented in the Statement of Financial Condition, Total Liabilities	0	0
Financial Instruments, Liabilities	0	0
Cash Collateral Received/Pledged, Liabilities	0	0
Net Amount, Liabilities	$0	$0

Derivatives_and_Hedging_Summar

Derivatives and Hedging - Summary of Gross Fair Values of Derivative Instruments (Detail) (Forward Contracts [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
Trading Activity, Gains and Losses, Net [Line Items]
Total unrealized appreciation on open forward contracts, Fair Value	$6,499,773	$5,969,177
Total unrealized depreciation on open forward contracts, Fair Value	-6,351,074	-3,229,324
Net unrealized appreciation on open forward contracts	148,699	2,739,853
Currencies [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Total unrealized appreciation on open forward contracts, Fair Value	6,499,773	5,969,177
Total unrealized depreciation on open forward contracts, Fair Value	($6,351,074)	($3,229,324)

Derivatives_and_Hedging_Summar1

Derivatives and Hedging - Summary of Trading Gains and Losses, by Market Sector, on Derivatives Instruments (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Trading Activity, Gains and Losses, Net [Line Items]
Trading gains and losses, by market sector	$885,009	$225,441
Cambridge Master Fund [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Trading gains and losses, by market sector	2,512,143	156,075
Cambridge Master Fund [Member] | Currencies [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Trading gains and losses, by market sector	$2,512,143	$156,075

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (Cambridge Master Fund [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
Cambridge Master Fund [Member]
Derivatives, Fair Value [Line Items]
Transfers of assets or liabilities between Level 1 and Level 2	$0	$0

Fair_Value_Measurements_Assets

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], Cambridge Master Fund [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
Assets
Forwards	$6,499,773	$5,969,177
Total Assets	6,499,773	5,969,177
Liabilities
Forwards	-6,351,074	3,229,324
Total Liabilities	-6,351,074	3,229,324
Net fair value	148,699	2,739,853
Level 2 [Member]
Assets
Forwards	6,499,773	5,969,177
Total Assets	6,499,773	5,969,177
Liabilities
Forwards	-6,351,074	3,229,324
Total Liabilities	-6,351,074	3,229,324
Net fair value	$148,699	$2,739,853