Investments - Summary of Partnership's Investments (Detail) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Management fees	$ 1,278,401	$ 1,923,032	$ 1,984,202
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partners' Capital	107.88%	102.85%
Fair Value	$ 17,075,116	$ 25,260,063
Management fees	238,151	$ 177,872	312,606
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member] \| Morgan Stanley Smith Barney BHM I, LLC [Member]
Schedule of Investments [Line Items]
Percentage of Partners' Capital		15.86%
Fair Value		$ 3,894,858
Partnership's Pro-rata Net Income (Loss)	(335,552)	(3,328,835)
Management fees	$ 6,470	$ 284,061
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemptions Permitted	Monthly	Monthly
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member] \| Pgr Master Fund Lp [Member]
Schedule of Investments [Line Items]
Percentage of Partners' Capital	50.79%	50.66%
Fair Value	$ 8,039,156	$ 12,442,510
Partnership's Pro-rata Net Income (Loss)	$ (904,136)	$ 104,616
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemptions Permitted	Monthly	Monthly
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member] \| MB Master Fund LP [Member]
Schedule of Investments [Line Items]
Percentage of Partners' Capital	57.09%	36.33%
Fair Value	$ 9,035,960	$ 8,922,695
Partnership's Pro-rata Net Income (Loss)	$ 1,259,981	$ (536,287)
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemptions Permitted	Monthly	Monthly
Morgan Stanley Smith Barney Spectrum Technical L.P. [Member]
Schedule of Investments [Line Items]
Management fees	$ 1,244,716	$ 1,581,367	$ 1,431,344
Morgan Stanley Smith Barney Spectrum Technical L.P. [Member] \| SECOR Master Fund [Member]
Schedule of Investments [Line Items]
Percentage of Partners' Capital	31.20%	30.40%
Fair Value	$ 19,624,189	$ 27,517,405
Partnership's Pro-rata Net Income (Loss)	$ 1,289,132	$ 855,249
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemptions Permitted	Monthly	Monthly
Morgan Stanley Smith Barney Spectrum Technical L.P. [Member] \| Blackwater Master Fund [Member]
Schedule of Investments [Line Items]
Partnership's Pro-rata Net Income (Loss)		$ (26,849)
Investment Objective		Commodity Portfolio
Redemptions Permitted		Monthly

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Investment Objective

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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.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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Amount of expenses related to the 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

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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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=65897068&loc=SL4591551-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 810
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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