DWS Treasury Portfolio Expense Example - Institutional Shares [Member] - DWS Treasury Portfolio - Institutional Shares	Jul. 28, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 26
Expense Example, with Redemption, 3 Years	89
Expense Example, with Redemption, 5 Years	159
Expense Example, with Redemption, 10 Years	$ 364

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