Administrative fee rate payable by the partnership to the general partner, annual basis.

No definition available.

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- Definition

Administrative fee rate payable by the partnership to the general partner, monthly basis.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The percentage amount of units that limited partners can redeemed.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Basis amount of assets not deposited as margin with a Partnership interest used in the calculation of interest income.

+ References

No definition available.

+ Details

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

- Definition

For Partnership Capital Units redemptions, the charge amount paid associated with the redemption based on the net asset value of the units redeemed at redemption date.

+ References

No definition available.

+ Details

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Namespace Prefix:	dwsf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Basis amount of funds on deposit with a Partnership interest used in the calculation of interest income.

+ References

No definition available.

+ Details

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

- Definition

For the first specific period for redemption, Partnership redemption charge as percentage basis of total net asset value.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

For a second specific period for redemption, Partnership redemption charge as percentage basis of total net asset value.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

The number of units or equivalent units required for an effective redemption for all classes of units.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Total distributions to each class of partners (i.e., general, limited and preferred partners).

+ References

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

-Publisher AICPA

-Name Practice Bulletin (PB)

-Number 14

-Paragraph 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187171-122770

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 87-21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash received for the settlement of litigation during the current period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 27

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3536-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Summary of Significant Accounting Policies (Details) (USD $)	1 Months Ended		12 Months Ended
	Sep. 30, 2011	Jul. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Equity Method Investments [Line Items]
Percentage basis of funds on deposit for interest income recognition (in hundredths)			100.00%
Partnership assets percentage not deposited as margin credit for interest income (in hundredths)			80.00%
MS&Co flat rate monthly brokerage fee on net assets (in hundredths)			0.50%
MS&Co flat rate annual brokerage fee on net assets (in hundredths)			6.00%
Limited partners unit that can be redeemed (in hundredths)			100.00%
Whole Units required per redemption (in units)			50
Percentage of net asset value, redemption charge prior to last day of twelfth month from date of purchase (in hundredths)			2.00%
Percentage of net asset value, redemption charge after the last day of twelfth month from date of purchase (in hundredths)			1.00%
Aggregate amount of redemption charges paid			$ 0	$ 0	$ 25,528
Distributions			0
Income tax expense (benefit)			0
Unrecognized tax benefit			0	0
Settlement award payment		337,120
Morgan Stanley Smith Barney Spectrum Currency and Commodity L.P. [Member]
Schedule of Equity Method Investments [Line Items]
Partnership assets percentage not deposited as margin credit for interest income (in hundredths)			80.00%
MS&Co flat rate monthly brokerage fee on net assets (in hundredths)			0.383%
MS&Co flat rate annual brokerage fee on net assets (in hundredths)			4.60%
Aggregate amount of redemption charges paid			0	0	1,653
Morgan Stanley Smith Barney Spectrum Global Balanced L.P. [Member]
Schedule of Equity Method Investments [Line Items]
Partnership assets percentage not deposited as margin credit for interest income (in hundredths)			100.00%
MS&Co flat rate monthly brokerage fee on net assets (in hundredths)			0.383%
MS&Co flat rate annual brokerage fee on net assets (in hundredths)			4.60%
Aggregate amount of redemption charges paid			0	0	767
Settlement award payment		29,602
Morgan Stanley Smith Barney Spectrum Strategic L.P. [Member]
Schedule of Equity Method Investments [Line Items]
Partnership assets percentage not deposited as margin credit for interest income (in hundredths)			80.00%
MS&Co flat rate monthly brokerage fee on net assets (in hundredths)			0.50%
MS&Co flat rate annual brokerage fee on net assets (in hundredths)			6.00%
Aggregate amount of redemption charges paid			0	0	8,019
Settlement award payment		220,755
Morgan Stanley Smith Barney Spectrum Technical L.P. [Member]
Schedule of Equity Method Investments [Line Items]
Partnership assets percentage not deposited as margin credit for interest income (in hundredths)			80.00%
MS&Co flat rate monthly brokerage fee on net assets (in hundredths)			0.50%
MS&Co flat rate annual brokerage fee on net assets (in hundredths)			6.00%
Aggregate amount of redemption charges paid			0	0	9,992
Settlement award payment	$ 10,951	$ 164,828