This semi-annual shareholder report contains important information about DWS RREEF Global Real Estate Securities Fund (the "Fund") for the period January 1, 2026 to June 30, 2026.

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

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Expenses [Text Block]

What were the Fund costs for the last six months?

(Based on a hypothetical $10,000 investment)

Table Summary
Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class A	$59	1.14%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 1.43%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 59

Expense Ratio, Percent

1.14%

^[1]

AssetsNet

$ 211,931,413

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 512,103

InvestmentCompanyPortfolioTurnover

56.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
Net Assets ($)	211,931,413
Number of Portfolio Holdings	97
Portfolio Turnover Rate (%)	56
Total Net Advisory Fees Paid ($)	512,103

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Table Summary
Asset Type	% of Net Assets
Common Stocks	99%
Cash Equivalents	0%
Other Assets and Liabilities, Net	1%
Total	100%

Sector Allocation

Table Summary
Sector	% of Net Assets
Specialized REITs	18%
Retail REITs	18%
Health Care REITs	15%
Industrial REITs	15%
Real Estate Management & Development	10%
Residential REITs	9%
Diversified REITs	8%
Office REITs	3%
Hotel & Resort REITs	3%
IT Services	0%

Geographical Diversification

Table Summary
Country	% of Net Assets
United States	66%
Japan	8%
Australia	6%
Singapore	3%
United Kingdom	3%
Hong Kong	3%
France	2%
Canada	2%
Switzerland	2%
Germany	1%
Other	3%

Ten Largest Equity Holdings

Table Summary
Holdings	40.2% of Net Assets
Welltower, Inc. (United States)	8.4%
Prologis, Inc. (United States)	6.5%
Equinix, Inc. (United States)	6.1%
Equity Residential (United States)	3.9%
Simon Property Group, Inc. (United States)	3.6%
Iron Mountain, Inc. (United States)	2.7%
Goodman Group (Australia)	2.3%
Public Storage (United States)	2.3%
Host Hotels & Resorts, Inc. (United States)	2.3%
Digital Realty Trust, Inc. (United States)	2.1%

C000099781

Shareholder Report [Line Items]

Fund Name

DWS RREEF Global Real Estate Securities Fund

Class Name

Class C

Trading Symbol

RRGCX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS RREEF Global Real Estate Securities Fund (the "Fund") for the period January 1, 2026 to June 30, 2026.

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)

Table Summary
Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class C	$98	1.89%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 2.13%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 98

Expense Ratio, Percent

1.89%

^[2]

AssetsNet

$ 211,931,413

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 512,103

InvestmentCompanyPortfolioTurnover

56.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
Net Assets ($)	211,931,413
Number of Portfolio Holdings	97
Portfolio Turnover Rate (%)	56
Total Net Advisory Fees Paid ($)	512,103

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Table Summary
Asset Type	% of Net Assets
Common Stocks	99%
Cash Equivalents	0%
Other Assets and Liabilities, Net	1%
Total	100%

Sector Allocation

Table Summary
Sector	% of Net Assets
Specialized REITs	18%
Retail REITs	18%
Health Care REITs	15%
Industrial REITs	15%
Real Estate Management & Development	10%
Residential REITs	9%
Diversified REITs	8%
Office REITs	3%
Hotel & Resort REITs	3%
IT Services	0%

Geographical Diversification

Table Summary
Country	% of Net Assets
United States	66%
Japan	8%
Australia	6%
Singapore	3%
United Kingdom	3%
Hong Kong	3%
France	2%
Canada	2%
Switzerland	2%
Germany	1%
Other	3%

Ten Largest Equity Holdings

Table Summary
Holdings	40.2% of Net Assets
Welltower, Inc. (United States)	8.4%
Prologis, Inc. (United States)	6.5%
Equinix, Inc. (United States)	6.1%
Equity Residential (United States)	3.9%
Simon Property Group, Inc. (United States)	3.6%
Iron Mountain, Inc. (United States)	2.7%
Goodman Group (Australia)	2.3%
Public Storage (United States)	2.3%
Host Hotels & Resorts, Inc. (United States)	2.3%
Digital Realty Trust, Inc. (United States)	2.1%

C000176653

Shareholder Report [Line Items]

Fund Name

DWS RREEF Global Real Estate Securities Fund

Class Name

Class R6

Trading Symbol

RRGRX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS RREEF Global Real Estate Securities Fund (the "Fund") for the period January 1, 2026 to June 30, 2026.

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)

Table Summary
Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$41	0.79%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 0.97%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 41

Expense Ratio, Percent

0.79%

^[3]

AssetsNet

$ 211,931,413

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 512,103

InvestmentCompanyPortfolioTurnover

56.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
Net Assets ($)	211,931,413
Number of Portfolio Holdings	97
Portfolio Turnover Rate (%)	56
Total Net Advisory Fees Paid ($)	512,103

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Table Summary
Asset Type	% of Net Assets
Common Stocks	99%
Cash Equivalents	0%
Other Assets and Liabilities, Net	1%
Total	100%

Sector Allocation

Table Summary
Sector	% of Net Assets
Specialized REITs	18%
Retail REITs	18%
Health Care REITs	15%
Industrial REITs	15%
Real Estate Management & Development	10%
Residential REITs	9%
Diversified REITs	8%
Office REITs	3%
Hotel & Resort REITs	3%
IT Services	0%

Geographical Diversification

Table Summary
Country	% of Net Assets
United States	66%
Japan	8%
Australia	6%
Singapore	3%
United Kingdom	3%
Hong Kong	3%
France	2%
Canada	2%
Switzerland	2%
Germany	1%
Other	3%

Ten Largest Equity Holdings

Table Summary
Holdings	40.2% of Net Assets
Welltower, Inc. (United States)	8.4%
Prologis, Inc. (United States)	6.5%
Equinix, Inc. (United States)	6.1%
Equity Residential (United States)	3.9%
Simon Property Group, Inc. (United States)	3.6%
Iron Mountain, Inc. (United States)	2.7%
Goodman Group (Australia)	2.3%
Public Storage (United States)	2.3%
Host Hotels & Resorts, Inc. (United States)	2.3%
Digital Realty Trust, Inc. (United States)	2.1%

C000099783

Shareholder Report [Line Items]

Fund Name

DWS RREEF Global Real Estate Securities Fund

Class Name

Class S

Trading Symbol

RRGTX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS RREEF Global Real Estate Securities Fund (the "Fund") for the period January 1, 2026 to June 30, 2026.

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)

Table Summary
Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class S	$52	0.99%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 1.20%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 52

Expense Ratio, Percent

0.99%

^[4]

AssetsNet

$ 211,931,413

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 512,103

InvestmentCompanyPortfolioTurnover

56.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
Net Assets ($)	211,931,413
Number of Portfolio Holdings	97
Portfolio Turnover Rate (%)	56
Total Net Advisory Fees Paid ($)	512,103

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Table Summary
Asset Type	% of Net Assets
Common Stocks	99%
Cash Equivalents	0%
Other Assets and Liabilities, Net	1%
Total	100%

Sector Allocation

Table Summary
Sector	% of Net Assets
Specialized REITs	18%
Retail REITs	18%
Health Care REITs	15%
Industrial REITs	15%
Real Estate Management & Development	10%
Residential REITs	9%
Diversified REITs	8%
Office REITs	3%
Hotel & Resort REITs	3%
IT Services	0%

Geographical Diversification

Table Summary
Country	% of Net Assets
United States	66%
Japan	8%
Australia	6%
Singapore	3%
United Kingdom	3%
Hong Kong	3%
France	2%
Canada	2%
Switzerland	2%
Germany	1%
Other	3%

Ten Largest Equity Holdings

Table Summary
Holdings	40.2% of Net Assets
Welltower, Inc. (United States)	8.4%
Prologis, Inc. (United States)	6.5%
Equinix, Inc. (United States)	6.1%
Equity Residential (United States)	3.9%
Simon Property Group, Inc. (United States)	3.6%
Iron Mountain, Inc. (United States)	2.7%
Goodman Group (Australia)	2.3%
Public Storage (United States)	2.3%
Host Hotels & Resorts, Inc. (United States)	2.3%
Digital Realty Trust, Inc. (United States)	2.1%

C000099784

Shareholder Report [Line Items]

Fund Name

DWS RREEF Global Real Estate Securities Fund

Class Name

Institutional Class

Trading Symbol

RRGIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about DWS RREEF Global Real Estate Securities Fund (the "Fund") for the period January 1, 2026 to June 30, 2026.

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)

Table Summary
Fund	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Institutional Class	$44	0.85%^{Footnote Reference(a)}

Footnote	Description
Footnote^(a)	Annualized.

Gross expense ratio as of the latest prospectus: 1.07%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount

$ 44

Expense Ratio, Percent

0.85%

^[5]

AssetsNet

$ 211,931,413

Holdings Count | Holding

Advisory Fees Paid, Amount

$ 512,103

InvestmentCompanyPortfolioTurnover

56.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
Net Assets ($)	211,931,413
Number of Portfolio Holdings	97
Portfolio Turnover Rate (%)	56
Total Net Advisory Fees Paid ($)	512,103

Holdings [Text Block]

What did the Fund invest in?

Asset Allocation

Table Summary
Asset Type	% of Net Assets
Common Stocks	99%
Cash Equivalents	0%
Other Assets and Liabilities, Net	1%
Total	100%

Sector Allocation

Table Summary
Sector	% of Net Assets
Specialized REITs	18%
Retail REITs	18%
Health Care REITs	15%
Industrial REITs	15%
Real Estate Management & Development	10%
Residential REITs	9%
Diversified REITs	8%
Office REITs	3%
Hotel & Resort REITs	3%
IT Services	0%

Geographical Diversification

Table Summary
Country	% of Net Assets
United States	66%
Japan	8%
Australia	6%
Singapore	3%
United Kingdom	3%
Hong Kong	3%
France	2%
Canada	2%
Switzerland	2%
Germany	1%
Other	3%

Ten Largest Equity Holdings

Table Summary
Holdings	40.2% of Net Assets
Welltower, Inc. (United States)	8.4%
Prologis, Inc. (United States)	6.5%
Equinix, Inc. (United States)	6.1%
Equity Residential (United States)	3.9%
Simon Property Group, Inc. (United States)	3.6%
Iron Mountain, Inc. (United States)	2.7%
Goodman Group (Australia)	2.3%
Public Storage (United States)	2.3%
Host Hotels & Resorts, Inc. (United States)	2.3%
Digital Realty Trust, Inc. (United States)	2.1%

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