v3.25.2
DWS Tax-Exempt Portfolio Annual Fund Operating Expenses - DWS Tax Expt Cash Prmr Shrs [Member] - DWS Tax-Exempt Portfolio
Apr. 30, 2025
Prospectus [Line Items]  
Fee Waiver or Reimbursement over Assets, Date of Termination <span style="font-family:Arial;font-size:10pt;"> July 31, </span><span style="font-family:Arial;font-size:10pt;">2026</span>
DWS Tax-Exempt Cash Premier Shares  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.07%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.35%
Expenses (as a percentage of Assets) 0.42%
Fee Waiver or Reimbursement (0.22%)
Net Expenses (as a percentage of Assets) 0.20%