DWS Tax-Exempt Portfolio Average Annual Total Returns - Service Shares [Member] - Service 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 | 2.27% | 1.05% | 0.62% | |
| Performance Inception Date | May 13, 2005 |