DWS Government and Agency Securities Portfolio Expense Example - Service Shares [Member] - DWS Government and Agency Securities Portfolio - Service Shares	Jul. 28, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 107
Expense Example, with Redemption, 3 Years	334
Expense Example, with Redemption, 5 Years	579
Expense Example, with Redemption, 10 Years	$ 1,283

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
-Subsection instruction
-Paragraph 4

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Balance Type:	na
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
-Subsection instruction
-Paragraph 4

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Namespace Prefix:	oef_
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
-Subsection instruction
-Paragraph 4

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Namespace Prefix:	oef_
Data Type:	dtr-types:nonNegativeMonetaryItemType
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
-Subsection instruction
-Paragraph 4

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Namespace Prefix:	oef_
Data Type:	dtr-types:nonNegativeMonetaryItemType
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 1
-Subsection a

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Namespace Prefix:
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