v3.25.2
DWS Government and Agency Securities Portfolio Average Annual Total Returns - Government Cash Managed Shares [Member] - Government Cash Managed Shares - Return Before Taxes[Member]
12 Months Ended 60 Months Ended 120 Months Ended
Apr. 30, 2025
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Prospectus [Line Items]        
Average Annual Return, Percent   4.97% 2.27% 1.54%
Performance Inception Date Feb. 16, 2007