This semi-annual shareholder report contains important information about DWS Treasury Portfolio (the "Fund") for the period April 1, 2025 to September 30, 2025.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund on the Fund's website at dws.com/mutualreports. You can also request this information by contacting us at (800) 730-1313.

Additional Information Phone Number

(800) 730-1313

Additional Information Website

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Expenses [Text Block]

What were the Fund costs for the last six months?

(Based on a hypothetical $10,000 investment)

Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Capital Shares	$10	0.20%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 0.33%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 10

Expense Ratio, Percent

0.20%

^[1]

AssetsNet

$ 585,599,970

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 53,180

Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)	585,599,970
Number of Portfolio Holdings	32
Total Net Advisory Fees Paid ($)	53,180
Weighted Average Maturity	20 days
7-Day Current Yield	3.98%

Weighted average maturity, also known as effective maturity, is the weighted average of the maturity date of bonds held by the Fund taking into consideration any available maturity shortening features.

Yields fluctuate and are not guaranteed. The 7-day current yield is the annualized net investment income per share as of September 30, 2025. The 7-Day Current Yield would have been 3.82% had certain expenses not been reduced.

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Asset Type	% of Net Assets
Government & Agency Obligations	51%
Repurchase Agreements	48%
Other Assets and Liabilities, Net	1%
Total	100%

Holdings-based data is subject to change.

C000035153

Shareholder Report [Line Items]

Fund Name

DWS Treasury Portfolio

Class Name

DWS U.S. Treasury Money Fund Class S

Trading Symbol

IUSXX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS Treasury Portfolio (the "Fund") for the period April 1, 2025 to September 30, 2025.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund on the Fund's website at dws.com/mutualreports. You can also request this information by contacting us at (800) 728-3337.

Additional Information Phone Number

(800) 728-3337

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(Based on a hypothetical $10,000 investment)

Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
DWS U.S. Treasury Money Fund Class S	$13	0.26%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 0.30%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 13

Expense Ratio, Percent

0.26%

^[2]

AssetsNet

$ 585,599,970

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 53,180

Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)	585,599,970
Number of Portfolio Holdings	32
Total Net Advisory Fees Paid ($)	53,180
Weighted Average Maturity	20 days
7-Day Current Yield	3.91%

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Asset Type	% of Net Assets
Government & Agency Obligations	51%
Repurchase Agreements	48%
Other Assets and Liabilities, Net	1%
Total	100%

Holdings-based data is subject to change.

C000017365

Shareholder Report [Line Items]

Fund Name

DWS Treasury Portfolio

Class Name

Institutional Shares

Trading Symbol

ICTXX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS Treasury Portfolio (the "Fund") for the period April 1, 2025 to September 30, 2025.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund on the Fund's website at dws.com/mutualreports. You can also request this information by contacting us at (800) 730-1313.

Additional Information Phone Number

(800) 730-1313

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(Based on a hypothetical $10,000 investment)

Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Institutional Shares	$9	0.17%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 0.30%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 9

Expense Ratio, Percent

0.17%

^[3]

AssetsNet

$ 585,599,970

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 53,180

Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)	585,599,970
Number of Portfolio Holdings	32
Total Net Advisory Fees Paid ($)	53,180
Weighted Average Maturity	20 days
7-Day Current Yield	3.97%

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Asset Type	% of Net Assets
Government & Agency Obligations	51%
Repurchase Agreements	48%
Other Assets and Liabilities, Net	1%
Total	100%

Holdings-based data is subject to change.

C000035154

Shareholder Report [Line Items]

Fund Name

DWS Treasury Portfolio

Class Name

Investment Class Shares

Trading Symbol

ITVXX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS Treasury Portfolio (the "Fund") for the period April 1, 2025 to September 30, 2025.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund on the Fund's website at dws.com/mutualreports. You can also request this information by contacting us at (800) 730-1313.

Additional Information Phone Number

(800) 730-1313

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(Based on a hypothetical $10,000 investment)

Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Investment Class Shares	$27	0.54%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 0.59%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 27

Expense Ratio, Percent

0.54%

^[4]

AssetsNet

$ 585,599,970

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 53,180

Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)	585,599,970
Number of Portfolio Holdings	32
Total Net Advisory Fees Paid ($)	53,180
Weighted Average Maturity	20 days
7-Day Current Yield	3.65%

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Asset Type	% of Net Assets
Government & Agency Obligations	51%
Repurchase Agreements	48%
Other Assets and Liabilities, Net	1%
Total	100%

Holdings-based data is subject to change.

[1]	Annualized.
[2]	Annualized.
[3]	Annualized.
[4]	Annualized.