v3.26.1
Shareholder Report
 6 Months Ended
Jan. 31, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name DEUTSCHE DWS INVESTMENT TRUST
Entity Central Index Key 0000088064
Entity Investment Company Type N-1A
Document Period End Date Jan. 31, 2026
Shareholder Report Annual or Semi-Annual Semi-Annual Shareholder Report
C000015684  
Shareholder Report [Line Items]  
Fund Name DWS Large Cap Focus Growth Fund
Class Name Class A
Trading Symbol SGGAX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about DWS Large Cap Focus Growth Fund (the "Fund") for the period August 1, 2025 to January 31, 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 <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 14.6667px; font-weight: 300; grid-area: auto; line-height: 17.6px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">dws.com/mutualreports</span>
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
Class A
$54
1.05%Footnote Reference(a)
FootnoteDescription
Footnote(a)
Annualized.

Gross expense ratio as of the latest prospectus: 1.15%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount $ 54
Expense Ratio, Percent 1.05% [1]
AssetsNet $ 390,509,837
Holdings Count | Holding 55
Advisory Fees Paid, Amount $ 1,252,242
InvestmentCompanyPortfolioTurnover 12.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)
390,509,837
Number of Portfolio Holdings
55
Portfolio Turnover Rate (%)
12
Total Net Advisory Fees Paid ($)
1,252,242
Holdings [Text Block]

Sector Allocation

Sector
% of Net Assets
Information Technology
48%
Communication Services
14%
Industrials
11%
Health Care
11%
Consumer Discretionary
8%
Financials
4%
Real Estate
2%
Consumer Staples
1%
C000015687  
Shareholder Report [Line Items]  
Fund Name DWS Large Cap Focus Growth Fund
Class Name Class C
Trading Symbol SGGCX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about DWS Large Cap Focus Growth Fund (the "Fund") for the period August 1, 2025 to January 31, 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 <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 14.6667px; font-weight: 300; grid-area: auto; line-height: 17.6px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">dws.com/mutualreports</span>
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
Class C
$92
1.80%Footnote Reference(a)
FootnoteDescription
Footnote(a)
Annualized.

Gross expense ratio as of the latest prospectus: 1.92%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount $ 92
Expense Ratio, Percent 1.80% [2]
AssetsNet $ 390,509,837
Holdings Count | Holding 55
Advisory Fees Paid, Amount $ 1,252,242
InvestmentCompanyPortfolioTurnover 12.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)
390,509,837
Number of Portfolio Holdings
55
Portfolio Turnover Rate (%)
12
Total Net Advisory Fees Paid ($)
1,252,242
Holdings [Text Block]

Sector Allocation

Sector
% of Net Assets
Information Technology
48%
Communication Services
14%
Industrials
11%
Health Care
11%
Consumer Discretionary
8%
Financials
4%
Real Estate
2%
Consumer Staples
1%
C000015689  
Shareholder Report [Line Items]  
Fund Name DWS Large Cap Focus Growth Fund
Class Name Class S
Trading Symbol SCQGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about DWS Large Cap Focus Growth Fund (the "Fund") for the period August 1, 2025 to January 31, 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 <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 14.6667px; font-weight: 300; grid-area: auto; line-height: 17.6px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">dws.com/mutualreports</span>
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
Class S
$41
0.80%Footnote Reference(a)
FootnoteDescription
Footnote(a)
Annualized.

Gross expense ratio as of the latest prospectus: 0.87%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount $ 41
Expense Ratio, Percent 0.80% [3]
AssetsNet $ 390,509,837
Holdings Count | Holding 55
Advisory Fees Paid, Amount $ 1,252,242
InvestmentCompanyPortfolioTurnover 12.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)
390,509,837
Number of Portfolio Holdings
55
Portfolio Turnover Rate (%)
12
Total Net Advisory Fees Paid ($)
1,252,242
Holdings [Text Block]

Sector Allocation

Sector
% of Net Assets
Information Technology
48%
Communication Services
14%
Industrials
11%
Health Care
11%
Consumer Discretionary
8%
Financials
4%
Real Estate
2%
Consumer Staples
1%
C000015690  
Shareholder Report [Line Items]  
Fund Name DWS Large Cap Focus Growth Fund
Class Name Institutional Class
Trading Symbol SGGIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about DWS Large Cap Focus Growth Fund (the "Fund") for the period August 1, 2025 to January 31, 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 <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 14.6667px; font-weight: 300; grid-area: auto; line-height: 17.6px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">dws.com/mutualreports</span>
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 Class
$41
0.80%Footnote Reference(a)
FootnoteDescription
Footnote(a)
Annualized.

Gross expense ratio as of the latest prospectus: 0.90%. See prospectus for any contractual or voluntary waivers; without a waiver, costs would have been higher.

Expenses Paid, Amount $ 41
Expense Ratio, Percent 0.80% [4]
AssetsNet $ 390,509,837
Holdings Count | Holding 55
Advisory Fees Paid, Amount $ 1,252,242
InvestmentCompanyPortfolioTurnover 12.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Net Assets ($)
390,509,837
Number of Portfolio Holdings
55
Portfolio Turnover Rate (%)
12
Total Net Advisory Fees Paid ($)
1,252,242
Holdings [Text Block]

Sector Allocation

Sector
% of Net Assets
Information Technology
48%
Communication Services
14%
Industrials
11%
Health Care
11%
Consumer Discretionary
8%
Financials
4%
Real Estate
2%
Consumer Staples
1%
[1] Annualized.
[2] Annualized.
[3] Annualized.
[4] Annualized.