Investments - Summary of Partnership's Investments (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Investments [Line Items]
Management Fees	$ 1,923,032	$ 1,984,202	$ 3,176,170
Morgan Stanley Smith Barney Spectrum Technical L.P. [Member]
Schedule of Investments [Line Items]
Management Fees	1,581,367	1,431,344	2,127,948
Morgan Stanley Smith Barney Spectrum Currency and Commodity L.P. [Member]
Schedule of Investments [Line Items]
Management Fees	$ 205,415	$ 205,572	346,230
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	102.85%	103.71%
Fair Value	$ 25,260,063	$ 37,031,024
Management Fees	$ 177,872	$ 312,606	$ 1,753,124
BHM I, LLC [Member] \| Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	15.86%	79.08%
Fair Value	$ 3,894,858	$ 28,236,607
Partnership's Pro-rata Net Income (Loss)	(3,328,835)	1,881,303
Management Fees	$ 284,061	$ 619,883
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemption Permitted	Monthly	Monthly
PGR Master Fund [Member] \| Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	50.66%	14.82%
Fair Value	$ 12,442,510	$ 5,291,425
Partnership's Pro-rata Net Income (Loss)	$ 104,616	$ 1,226,334
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemption Permitted	Monthly	Monthly
MB Master Fund [Member] \| Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	36.33%	9.81%
Fair Value	$ 8,922,695	$ 3,502,992
Partnership's Pro-rata Net Income (Loss)	$ (536,287)	$ 68,634
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemption Permitted	Monthly	Monthly
Blackwater Master Fund [Member] \| Morgan Stanley Smith Barney Spectrum Technical L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets		15.50%
Fair Value		$ 16,901,955
Partnership's Pro-rata Net Income (Loss)	$ (26,849)	$ (138,777)
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemption Permitted	Monthly	Monthly
SECOR Master Fund LP [Member] \| Morgan Stanley Smith Barney Spectrum Technical L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	30.45%
Fair Value	$ 27,517,405
Partnership's Pro-rata Net Income (Loss)	$ 855,249
Investment Objective	Commodity Portfolio
Redemption Permitted	Monthly
Cambridge Master Fund [Member] \| Morgan Stanley Smith Barney Spectrum Currency and Commodity L.P. [Member]
Schedule of Investments [Line Items]
Percentage of Partnership Net Assets	102.00%	89.30%
Fair Value	$ 13,537,489	$ 12,289,754
Partnership's Pro-rata Net Income (Loss)	$ 3,223,223	$ 2,777,719
Investment Objective	Commodity Portfolio	Commodity Portfolio
Redemption Permitted	Monthly	Monthly
KR Master Fund [Member] \| Morgan Stanley Smith Barney Spectrum Currency and Commodity L.P. [Member]
Schedule of Investments [Line Items]
Partnership's Pro-rata Net Income (Loss)		$ 156,507
Investment Objective		Commodity Portfolio
Redemption 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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=35736750&loc=SL4591551-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684

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