v3.25.4
Performance Management
Feb. 27, 2026
Janus Henderson Transformational Growth ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The Fund does not have a full calendar year of operations. When provided, the information is designed to offer some indication of the risks of investing in the Fund by showing how the Fund’s average annual returns compare with a broad measure of market performance. Past performance does not necessarily indicate how the Fund will perform in the future. Performance information for certain periods is included in the Fund’s annual and/or semiannual report and is available at janushenderson.com/info or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] Past performance does not necessarily indicate how the Fund will perform in the future.
Performance One Year or Less [Text] The Fund does not have a full calendar year of operations.
Performance Availability Website Address [Text] janushenderson.com/info
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Asset-Backed Securities ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The Fund does not have a full calendar year of operations. When provided, the information is designed to offer some indication of the risks of investing in the Fund by showing how the Fund’s average annual returns compare with a broad measure of market performance. Past performance does not necessarily indicate how the Fund will perform in the future. Performance information for certain periods is included in the Fund’s annual and/or semiannual report and is available at janushenderson.com/info or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] Past performance does not necessarily indicate how the Fund will perform in the future.
Performance Information Illustrates Variability of Returns [Text] When provided, the information is designed to offer some indication of the risks of investing in the Fund by showing how the Fund’s average annual returns compare with a broad measure of market performance.
Performance Availability Website Address [Text] janushenderson.com/info
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson AAA CLO ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

3rd Quarter 2023

2.55%

Worst Quarter:

2nd Quarter 2022

-1.75%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson AAA CLO ETF | Janus Henderson AAA CLO ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 2.55%
Highest Quarterly Return, Date Sep. 30, 2023
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (1.75%)
Lowest Quarterly Return, Date Jun. 30, 2022
Janus Henderson B-BBB CLO ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

3rd Quarter 2023

5.86%

Worst Quarter:

1st Quarter 2025

0.26%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Narrative

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred he after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson B-BBB CLO ETF | Janus Henderson B-BBB CLO ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 5.86%
Highest Quarterly Return, Date Sep. 30, 2023
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return 0.26%
Lowest Quarterly Return, Date Mar. 31, 2025
Janus Henderson Corporate Bond ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses. Effective May 13, 2024, the Fund changed its investment strategy. Performance prior to May 13, 2024, reflects the Fund’s former strategy; its performance may have differed if the Fund’s current strategy had been in place.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

4th Quarter 2023

9.13%

Worst Quarter:

1st Quarter 2022

-7.85%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Corporate Bond ETF | Janus Henderson Corporate Bond ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 9.13%
Highest Quarterly Return, Date Dec. 31, 2023
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (7.85%)
Lowest Quarterly Return, Date Mar. 31, 2022
Janus Henderson Emerging Markets Debt Hard Currency ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

3rd Quarter 2025

4.40%

Worst Quarter:

1st Quarter 2025

2.21%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Emerging Markets Debt Hard Currency ETF | Janus Henderson Corporate Bond ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 4.40%
Highest Quarterly Return, Date Sep. 30, 2025
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return 2.21%
Lowest Quarterly Return, Date Mar. 31, 2025
Janus Henderson Income ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

2nd Quarter 2025

2.36%

Worst Quarter:

4th Quarter 2025

1.60%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Income ETF | Janus Henderson Corporate Bond ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 2.36%
Highest Quarterly Return, Date Jun. 30, 2025
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return 1.60%
Lowest Quarterly Return, Date Dec. 31, 2025
Janus Henderson Mortgage-Backed Securities ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

4th Quarter 2023

7.72%

Worst Quarter:

3rd Quarter 2022

-5.43%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Narrative

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Mortgage-Backed Securities ETF | Janus Henderson Mortgage-Backed Securities ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 7.72%
Highest Quarterly Return, Date Dec. 31, 2023
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (5.43%)
Lowest Quarterly Return, Date Sep. 30, 2022
Janus Henderson Securitized Income ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

3rd Quarter 2024

3.92%

Worst Quarter:

4th Quarter 2024

0.25%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Securitized Income ETF | Janus Henderson Securitized Income ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 3.92%
Highest Quarterly Return, Date Sep. 30, 2024
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return 0.25%
Lowest Quarterly Return, Date Dec. 31, 2024
Janus Henderson Short Duration Income ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

2nd Quarter 2020

2.47%

Worst Quarter:

1st Quarter 2022

–0.88%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Market Index Changed Effective on or about October 7, 2025, the Fund changed the performance benchmark from the FTSE 3-Month U.S. Treasury Bill Index to the ICE BofA U.S. 3-Month Treasury Bill Total Return Index as it has investment characteristics similar to the Fund.
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Short Duration Income ETF | Janus Henderson Short Duration Income ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 2.47%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (0.88%)
Lowest Quarterly Return, Date Mar. 31, 2022
Janus Henderson Global Artificial Intelligence ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The Fund does not have a full calendar year of operations. When provided, the information is designed to offer some indication of the risks of investing in the Fund by showing how the Fund’s average annual returns compare with a broad measure of market performance. Past performance does not necessarily indicate how the Fund will perform in the future. Performance information for certain periods is included in the Fund’s annual and/or semiannual report and is available at janushenderson.com/info or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] Past performance does not necessarily indicate how the Fund will perform in the future.
Performance One Year or Less [Text] The Fund does not have a full calendar year of operations.
Performance Availability Website Address [Text] janushenderson.com/info
Performance Availability Phone [Text] 1-800-668-0434.
Janus Henderson U.S. Real Estate ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time.
Bar Chart Closing [Text Block]

 

  09/30/2024     06/30/2022  

Best Quarter:

3rd Quarter 2024

17.21%

Worst Quarter:

2nd Quarter 2022

-15.23%

Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson U.S. Real Estate ETF | Janus Henderson U.S. Real Estate ETF  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 17.21%
Highest Quarterly Return, Date Sep. 30, 2024
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (15.23%)
Lowest Quarterly Return, Date Jun. 30, 2022
Janus Henderson Mid Cap Growth Alpha ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

2nd Quarter 2025

13.34%

Worst Quarter:

1st Quarter 2025

-7.93%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Mid Cap Growth Alpha ETF | Janus Henderson Mid Cap Growth Alpha ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter
Highest Quarterly Return 13.34%
Highest Quarterly Return, Date Jun. 30, 2025
Lowest Quarterly Return, Label [Optional Text] Worst Quarter
Lowest Quarterly Return (7.93%)
Lowest Quarterly Return, Date Mar. 31, 2025
Janus Henderson Small Cap Growth Alpha ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses. Effective May 12, 2025, the Fund changed its investment strategy. Performance prior to May 12, 2025, reflects the Fund’s former strategy; its performance may have differed if the Fund’s current strategy had been in place.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

2nd Quarter 2020

34.62%

Worst Quarter:

1st Quarter 2020

-26.88%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Small Cap Growth Alpha ETF | Janus Henderson Small Cap Growth Alpha ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 34.62%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (26.88%)
Lowest Quarterly Return, Date Mar. 31, 2020
Janus Henderson Small/Mid Cap Growth Alpha ETF  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] PERFORMANCE INFORMATION
Performance Narrative [Text Block]

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions and include the effect of the Fund’s recurring expenses. Effective May 12, 2025, the Fund changed its investment strategy. Performance prior to May 12, 2025, reflects the Fund’s former strategy; its performance may have differed if the Fund’s current strategy had been in place.

 

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-800-668-0434.

Performance Past Does Not Indicate Future [Text] The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text] The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund.
Bar Chart [Heading] Annual Total Returns (calendar year-end)
Bar Chart Closing [Text Block]

 

Best Quarter:

2nd Quarter 2020

34.59%

Worst Quarter:

1st Quarter 2020

-25.89%

Performance Table Heading Average Annual Total Returns (periods ended 12/31/25)
Performance Table Uses Highest Federal Rate After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.
Performance Table Explanation after Tax Higher If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund’s other return figures.
Performance Table Closing [Text Block]

After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

Performance Availability Website Address [Text] janushenderson.com/performance
Performance Availability Phone [Text] 1-800-668-0434
Janus Henderson Small/Mid Cap Growth Alpha ETF | Janus Henderson Small/Mid Cap Growth Alpha ETF Shares  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] Best Quarter:
Highest Quarterly Return 34.59%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] Worst Quarter:
Lowest Quarterly Return (25.89%)
Lowest Quarterly Return, Date Mar. 31, 2020