DWS RREEF Completion Fund I Expense Example - DWS RREEF Completion Fund I - DWS RREEF Completion Fund I	Jul. 27, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 0
Expense Example, with Redemption, 3 Years	746
Expense Example, with Redemption, 5 Years	2,198
Expense Example, with Redemption, 10 Years	$ 5,600

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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