Name:	dwsf_CommodityProgramLeveragePercentage
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Data Type:	num:percentItemType
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Period Type:	instant

Investment Owned Percent

No definition available.

Name:	dwsf_InvestmentOwnedPercent
Namespace Prefix:	dwsf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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.

No definition available.

Name:	dwsf_InvestmentsInAndAdvancesToAffiliatesPercentageOfPartnerCapital
Namespace Prefix:	dwsf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The leverage applied to assets and traded pursuant to the diversified program.

No definition available.

Name:	dwsf_LeverageAppliedToAssets
Namespace Prefix:	dwsf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Number of trading vehicles organized as a systematic trading program for a Master Fund.

No definition available.

Name:	dwsf_MasterFundFormationOfTradingVehicles
Namespace Prefix:	dwsf_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.

Name:	us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix:	us-gaap_
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Name:	dei_LegalEntityAxis=dwsf_CeresTacticalCurrencyLPMember
Namespace Prefix:
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Name:	invest_InvestmentHoldingAxis=dwsf_CambridgeMasterFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentHoldingAxis=dwsf_KrMasterFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	dei_LegalEntityAxis=dwsf_MorganStanleySmithBarneySpectrumStrategicLPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	invest_InvestmentHoldingAxis=dwsf_BhmILlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	invest_InvestmentHoldingAxis=dwsf_PGRMasterFundLPMember
Namespace Prefix:
Data Type:	na
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Period Type:

Name:	invest_InvestmentHoldingAxis=dwsf_MbMasterFundLpMember
Namespace Prefix:
Data Type:	na
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Name:	dei_LegalEntityAxis=dwsf_MorganStanleySmithBarneySpectrumTechnicalLPMember
Namespace Prefix:
Data Type:	na
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Name:	invest_InvestmentHoldingAxis=dwsf_SecorMasterFundMember
Namespace Prefix:
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