v3.26.1
Shareholder Report
6 Months Ended
Apr. 30, 2026
USD ($)
Holdings
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name Hennessy Funds Trust
Entity Central Index Key 0000891944
Entity Investment Company Type N-1A
Document Period End Date Apr. 30, 2026
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Hennessy Cornerstone Growth Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Growth Fund
Class Name Investor Class
Trading Symbol HFCGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Growth Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$69
1.30%
*Annualized.
Expenses Paid, Amount $ 69
Expense Ratio, Percent 1.30% [1]
Net Assets $ 500,562,498
Holdings Count | Holdings 52
Investment Company, Portfolio Turnover 0.00% [2]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$500,562,498
Number of Portfolio Holdings
52
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector
%
Communication Services
0.14
Consumer Discretionary
0.079
Consumer Staples
0.201
Energy
0.019
Financials
0.277
Health Care
0.107
Industrials
0.107
Information Technology
0.027
Real Estate
0.017
Utilities
0.018
Short-Term Investments and Other
0.008
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Growth Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Growth Fund
Class Name Institutional Class
Trading Symbol HICGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Growth Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$52
0.98%
*Annualized.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.98% [3]
Net Assets $ 500,562,498
Holdings Count | Holdings 52
Investment Company, Portfolio Turnover 0.00% [4]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$500,562,498
Number of Portfolio Holdings
52
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector
%
Communication Services
0.14
Consumer Discretionary
0.079
Consumer Staples
0.201
Energy
0.019
Financials
0.277
Health Care
0.107
Industrials
0.107
Information Technology
0.027
Real Estate
0.017
Utilities
0.018
Short-Term Investments and Other
0.008
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Focus Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Focus Fund
Class Name Investor Class
Trading Symbol HFCSX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Focus Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$71
1.46%
*Annualized.
Expenses Paid, Amount $ 71
Expense Ratio, Percent 1.46% [5]
Net Assets $ 491,374,302
Holdings Count | Holdings 25
Investment Company, Portfolio Turnover 3.00% [6]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$491,374,302
Number of Portfolio Holdings
25
Annual Portfolio Turnover*
3%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
21.7%
Consumer Discretionary
16.7%
Financials
23.9%
Health Care
2.6%
Industrials
11.8%
Information Technology
11.7%
Real Estate
5.6%
Short-Term Investments and Other
6.0%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Focus Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Focus Fund
Class Name Institutional Class
Trading Symbol HFCIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Focus Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$54
1.12%
*Annualized.
Expenses Paid, Amount $ 54
Expense Ratio, Percent 1.12% [7]
Net Assets $ 491,374,302
Holdings Count | Holdings 25
Investment Company, Portfolio Turnover 3.00% [8]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$491,374,302
Number of Portfolio Holdings
25
Annual Portfolio Turnover*
3%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
21.7%
Consumer Discretionary
16.7%
Financials
23.9%
Health Care
2.6%
Industrials
11.8%
Information Technology
11.7%
Real Estate
5.6%
Short-Term Investments and Other
6.0%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Mid Cap 30 Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Mid Cap 30 Fund
Class Name Investor Class
Trading Symbol HFMDX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Mid Cap 30 Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$71
1.33%
*Annualized.
Expenses Paid, Amount $ 71
Expense Ratio, Percent 1.33% [9]
Net Assets $ 1,285,463,558
Holdings Count | Holdings 31
Investment Company, Portfolio Turnover 0.00% [10]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$1,285,463,558
Number of Portfolio Holdings
31
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
7.4%
Consumer Discretionary
19.3%
Consumer Staples
6.5%
Financials
4.7%
Industrials
34.1%
Information Technology
17.9%
Materials
2.9%
Real Estate
4.4%
Short-Term Investments and Other
2.8%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Mid Cap 30 Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Mid Cap 30 Fund
Class Name Institutional Class
Trading Symbol HIMDX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Mid Cap 30 Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$52
0.98%
*Annualized.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.98% [11]
Net Assets $ 1,285,463,558
Holdings Count | Holdings 31
Investment Company, Portfolio Turnover 0.00% [12]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$1,285,463,558
Number of Portfolio Holdings
31
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
7.4%
Consumer Discretionary
19.3%
Consumer Staples
6.5%
Financials
4.7%
Industrials
34.1%
Information Technology
17.9%
Materials
2.9%
Real Estate
4.4%
Short-Term Investments and Other
2.8%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Large Growth Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Large Growth Fund
Class Name Investor Class
Trading Symbol HFLGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Large Growth Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$65
1.27%
*Annualized.
Expenses Paid, Amount $ 65
Expense Ratio, Percent 1.27% [13]
Net Assets $ 137,067,528
Holdings Count | Holdings 51
Investment Company, Portfolio Turnover 60.00% [14]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$137,067,528
Number of Portfolio Holdings
51
Annual Portfolio Turnover*
60%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
1.9%
Consumer Discretionary
17.5%
Consumer Staples
15.7%
Energy
5.1%
Financials
17.6%
Health Care
15.9%
Industrials
11.8%
Information Technology
11.4%
Materials
1.8%
Short-Term Investments and Other
1.3%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Large Growth Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Large Growth Fund
Class Name Institutional Class
Trading Symbol HILGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Large Growth Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$50
0.98%
*Annualized.
Expenses Paid, Amount $ 50
Expense Ratio, Percent 0.98% [15]
Net Assets $ 137,067,528
Holdings Count | Holdings 51
Investment Company, Portfolio Turnover 60.00% [16]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$137,067,528
Number of Portfolio Holdings
51
Annual Portfolio Turnover*
60%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
1.9%
Consumer Discretionary
17.5%
Consumer Staples
15.7%
Energy
5.1%
Financials
17.6%
Health Care
15.9%
Industrials
11.8%
Information Technology
11.4%
Materials
1.8%
Short-Term Investments and Other
1.3%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Value Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Value Fund
Class Name Investor Class
Trading Symbol HFCVX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Value Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$65
1.21%
*Annualized.
Expenses Paid, Amount $ 65
Expense Ratio, Percent 1.21% [17]
Net Assets $ 330,241,183
Holdings Count | Holdings 51
Investment Company, Portfolio Turnover 19.00% [18]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$330,241,183
Number of Portfolio Holdings
51
Annual Portfolio Turnover*
19%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector
%
Communication Services
0.079
Consumer Discretionary
0.064
Consumer Staples
0.171
Energy
0.24
Financials
0.154
Health Care
0.199
Information Technology
0.084
Short-Term Investments and Other
0.009000000000000001
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Cornerstone Value Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Cornerstone Value Fund
Class Name Institutional Class
Trading Symbol HICVX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Cornerstone Value Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$54
1.00%
*Annualized.
Expenses Paid, Amount $ 54
Expense Ratio, Percent 1.00% [19]
Net Assets $ 330,241,183
Holdings Count | Holdings 51
Investment Company, Portfolio Turnover 19.00% [20]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$330,241,183
Number of Portfolio Holdings
51
Annual Portfolio Turnover*
19%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector
%
Communication Services
0.079
Consumer Discretionary
0.064
Consumer Staples
0.171
Energy
0.24
Financials
0.154
Health Care
0.199
Information Technology
0.084
Short-Term Investments and Other
0.009000000000000001
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Total Return Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Total Return Fund
Class Name Investor Class
Trading Symbol HDOGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Total Return Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$151
2.95%
*Annualized.
Expenses Paid, Amount $ 151
Expense Ratio, Percent 2.95% [21]
Net Assets $ 50,008,495
Holdings Count | Holdings 20
Investment Company, Portfolio Turnover 30.00% [22]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$50,008,495
Number of Portfolio Holdings
20
Annual Portfolio Turnover*
30%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
7.7%
Consumer Discretionary
13.3%
Consumer Staples
14.2%
Energy
7.7%
Health Care
25.3%
Information Technology
0.9%
Short-Term Investments and Other
30.9%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Equity and Income Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Equity and Income Fund
Class Name Investor Class
Trading Symbol HEIFX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Equity and Income Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$86
1.66%
*Annualized.
Expenses Paid, Amount $ 86
Expense Ratio, Percent 1.66% [23]
Net Assets $ 41,253,935
Holdings Count | Holdings 95
Investment Company, Portfolio Turnover 12.00% [24]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$41,253,935
Number of Portfolio Holdings
95
Annual Portfolio Turnover*
12%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
8.0%
Consumer Discretionary
5.3%
Consumer Staples
5.2%
Energy
2.9%
Financials
22.5%
Health Care
3.3%
Industrials
12.6%
Information Technology
14.0%
Materials
7.7%
Utilities
2.7%
Mortgage-Backed Securities
0.2%
U.S. Treasury Notes
13.6%
Short-Term Investments and Other
2.0%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Equity and Income Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Equity and Income Fund
Class Name Institutional Class
Trading Symbol HEIIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Equity and Income Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$68
1.31%
*Annualized.
Expenses Paid, Amount $ 68
Expense Ratio, Percent 1.31% [25]
Net Assets $ 41,253,935
Holdings Count | Holdings 95
Investment Company, Portfolio Turnover 12.00% [26]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$41,253,935
Number of Portfolio Holdings
95
Annual Portfolio Turnover*
12%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
8.0%
Consumer Discretionary
5.3%
Consumer Staples
5.2%
Energy
2.9%
Financials
22.5%
Health Care
3.3%
Industrials
12.6%
Information Technology
14.0%
Materials
7.7%
Utilities
2.7%
Mortgage-Backed Securities
0.2%
U.S. Treasury Notes
13.6%
Short-Term Investments and Other
2.0%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Balanced Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Balanced Fund
Class Name Investor Class
Trading Symbol HBFBX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Balanced Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$92
1.80%
*Annualized.
Expenses Paid, Amount $ 92
Expense Ratio, Percent 1.80% [27]
Net Assets $ 13,610,160
Holdings Count | Holdings 17
Investment Company, Portfolio Turnover 19.00% [28]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$13,610,160
Number of Portfolio Holdings
17
Annual Portfolio Turnover*
19%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
4.9%
Consumer Discretionary
5.0%
Consumer Staples
8.7%
Energy
6.0%
Health Care
20.9%
Information Technology
5.3%
Short-Term Investments and Other
49.2%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Energy Transition Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Energy Transition Fund
Class Name Investor Class
Trading Symbol HNRGX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Energy Transition Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$139
2.37%
*Annualized.
Expenses Paid, Amount $ 139
Expense Ratio, Percent 2.37% [29]
Net Assets $ 23,995,368
Holdings Count | Holdings 29
Investment Company, Portfolio Turnover 16.00% [30]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$23,995,368
Number of Portfolio Holdings
29
Annual Portfolio Turnover*
16%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Downstream
8.4%
Exploration and Production
32.8%
Integrated
9.3%
Materials
4.1%
Midstream
13.2%
Oil Services
24.5%
Utilities
4.5%
Short-Term Investments and Other
3.2%
bar

For presentation purposes, the Fund uses custom categories.

Hennessy Energy Transition Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Energy Transition Fund
Class Name Institutional Class
Trading Symbol HNRIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Energy Transition Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$121
2.07%
*Annualized.
Expenses Paid, Amount $ 121
Expense Ratio, Percent 2.07% [31]
Net Assets $ 23,995,368
Holdings Count | Holdings 29
Investment Company, Portfolio Turnover 16.00% [32]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$23,995,368
Number of Portfolio Holdings
29
Annual Portfolio Turnover*
16%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Downstream
8.4%
Exploration and Production
32.8%
Integrated
9.3%
Materials
4.1%
Midstream
13.2%
Oil Services
24.5%
Utilities
4.5%
Short-Term Investments and Other
3.2%
bar

For presentation purposes, the Fund uses custom categories.

Hennessy Midstream Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Midstream Fund
Class Name Investor Class
Trading Symbol HMSFX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Midstream Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$97
1.75%
*Annualized.
Expenses Paid, Amount $ 97
Expense Ratio, Percent 1.75% [33]
Net Assets $ 79,398,201
Holdings Count | Holdings 16
Investment Company, Portfolio Turnover 0.00% [34]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$79,398,201
Number of Portfolio Holdings
16
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Crude Oil and Refined Products
23.2%
Geathering and Processing
19.0%
Natural Gas/NGL Transportation
59.1%
Short-Term Investments and Other
-1.3%
bar

For presentation purposes, the Fund uses custom categories.

Hennessy Midstream Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Midstream Fund
Class Name Institutional Class
Trading Symbol HMSIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Midstream Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$80
1.44%
*Annualized.
Expenses Paid, Amount $ 80
Expense Ratio, Percent 1.44% [35]
Net Assets $ 79,398,201
Holdings Count | Holdings 16
Investment Company, Portfolio Turnover 0.00% [36]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$79,398,201
Number of Portfolio Holdings
16
Annual Portfolio Turnover*
0%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Crude Oil and Refined Products
23.2%
Geathering and Processing
19.0%
Natural Gas/NGL Transportation
59.1%
Short-Term Investments and Other
-1.3%
bar

For presentation purposes, the Fund uses custom categories.

Hennessy Gas Utility Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Gas Utility Fund
Class Name Investor Class
Trading Symbol GASFX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Gas Utility Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$52
0.97%
*Annualized.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.97% [37]
Net Assets $ 539,971,302
Holdings Count | Holdings 47
Investment Company, Portfolio Turnover 6.00% [38]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$539,971,302
Number of Portfolio Holdings
47
Annual Portfolio Turnover*
6%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Energy
38.7%
Financials
4.8%
Utilities
56.1%
Short-Term Investments and Other
0.4%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Gas Utility Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Gas Utility Fund
Class Name Institutional Class
Trading Symbol HGASX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Gas Utility Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$36
0.68%
*Annualized.
Expenses Paid, Amount $ 36
Expense Ratio, Percent 0.68% [39]
Net Assets $ 539,971,302
Holdings Count | Holdings 47
Investment Company, Portfolio Turnover 6.00% [40]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$539,971,302
Number of Portfolio Holdings
47
Annual Portfolio Turnover*
6%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Energy
38.7%
Financials
4.8%
Utilities
56.1%
Short-Term Investments and Other
0.4%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Japan Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Japan Fund
Class Name Investor Class
Trading Symbol HJPNX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Japan Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$71
1.39%
*Annualized.
Expenses Paid, Amount $ 71
Expense Ratio, Percent 1.39% [41]
Net Assets $ 447,550,466
Holdings Count | Holdings 31
Investment Company, Portfolio Turnover 3.00% [42]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$447,550,466
Number of Portfolio Holdings
31
Annual Portfolio Turnover*
3%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
5.1%
Consumer Discretionary
11.8%
Consumer Staples
5.9%
Financials
34.5%
Health Care
0.6%
Industrials
18.0%
Information Technology
12.6%
Materials
6.3%
Real Estate
1.9%
Short-Term Investments and Other
3.3%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Japan Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Japan Fund
Class Name Institutional Class
Trading Symbol HJPIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Japan Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$53
1.04%
*Annualized.
Expenses Paid, Amount $ 53
Expense Ratio, Percent 1.04% [43]
Net Assets $ 447,550,466
Holdings Count | Holdings 31
Investment Company, Portfolio Turnover 3.00% [44]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$447,550,466
Number of Portfolio Holdings
31
Annual Portfolio Turnover*
3%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
5.1%
Consumer Discretionary
11.8%
Consumer Staples
5.9%
Financials
34.5%
Health Care
0.6%
Industrials
18.0%
Information Technology
12.6%
Materials
6.3%
Real Estate
1.9%
Short-Term Investments and Other
3.3%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Japan Small Cap Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Japan Small Cap Fund
Class Name Investor Class
Trading Symbol HJPSX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Japan Small Cap Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$79
1.48%
*Annualized.
Expenses Paid, Amount $ 79
Expense Ratio, Percent 1.48% [45]
Net Assets $ 131,830,605
Holdings Count | Holdings 62
Investment Company, Portfolio Turnover 21.00% [46]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$131,830,605
Number of Portfolio Holdings
62
Annual Portfolio Turnover*
21%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
1.6%
Consumer Discretionary
18.9%
Consumer Staples
7.3%
Financials
9.9%
Health Care
2.8%
Industrials
31.4%
Information Technology
14.1%
Materials
4.8%
Real Estate
5.4%
Utilities
0.3%
Short-Term Investments and Other
3.5%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Japan Small Cap Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Japan Small Cap Fund
Class Name Institutional Class
Trading Symbol HJSIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Japan Small Cap Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$58
1.09%
*Annualized.
Expenses Paid, Amount $ 58
Expense Ratio, Percent 1.09% [47]
Net Assets $ 131,830,605
Holdings Count | Holdings 62
Investment Company, Portfolio Turnover 21.00% [48]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$131,830,605
Number of Portfolio Holdings
62
Annual Portfolio Turnover*
21%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
1.6%
Consumer Discretionary
18.9%
Consumer Staples
7.3%
Financials
9.9%
Health Care
2.8%
Industrials
31.4%
Information Technology
14.1%
Materials
4.8%
Real Estate
5.4%
Utilities
0.3%
Short-Term Investments and Other
3.5%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Large Cap Financial Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Large Cap Financial Fund
Class Name Investor Class
Trading Symbol HLFNX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Large Cap Financial Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$91
1.86%
*Annualized.
Expenses Paid, Amount $ 91
Expense Ratio, Percent 1.86% [49]
Net Assets $ 28,572,500
Holdings Count | Holdings 26
Investment Company, Portfolio Turnover 17.00% [50]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$28,572,500
Number of Portfolio Holdings
26
Annual Portfolio Turnover*
17%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Financials
98.1%
Short-Term Investments and Other
1.9%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Large Cap Financial Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Large Cap Financial Fund
Class Name Institutional Class
Trading Symbol HILFX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Large Cap Financial Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$76
1.54%
*Annualized.
Expenses Paid, Amount $ 76
Expense Ratio, Percent 1.54% [51]
Net Assets $ 28,572,500
Holdings Count | Holdings 26
Investment Company, Portfolio Turnover 17.00% [52]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$28,572,500
Number of Portfolio Holdings
26
Annual Portfolio Turnover*
17%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Financials
98.1%
Short-Term Investments and Other
1.9%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Small Cap Financial Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Small Cap Financial Fund
Class Name Investor Class
Trading Symbol HSFNX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Small Cap Financial Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$87
1.62%
*Annualized.
Expenses Paid, Amount $ 87
Expense Ratio, Percent 1.62% [53]
Net Assets $ 72,345,745
Holdings Count | Holdings 27
Investment Company, Portfolio Turnover 10.00% [54]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$72,345,745
Number of Portfolio Holdings
27
Annual Portfolio Turnover*
10%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Financials
99.1%
Short-Term Investments and Other
0.9%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Small Cap Financial Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Small Cap Financial Fund
Class Name Institutional Class
Trading Symbol HISFX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Small Cap Financial Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$70
1.30%
*Annualized.
Expenses Paid, Amount $ 70
Expense Ratio, Percent 1.30% [55]
Net Assets $ 72,345,745
Holdings Count | Holdings 27
Investment Company, Portfolio Turnover 10.00% [56]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$72,345,745
Number of Portfolio Holdings
27
Annual Portfolio Turnover*
10%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Financials
99.1%
Short-Term Investments and Other
0.9%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Technology Fund - Investor Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Technology Fund
Class Name Investor Class
Trading Symbol HTECX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Technology Fund – Investor Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Investor Class
$61
1.23%
*Annualized.
Expenses Paid, Amount $ 61
Expense Ratio, Percent 1.23% [57]
Net Assets $ 8,140,718
Holdings Count | Holdings 61
Investment Company, Portfolio Turnover 55.00% [58]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$8,140,718
Number of Portfolio Holdings
61
Annual Portfolio Turnover*
55%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
12.3%
Information Technology
85.1%
Short-Term Investments and Other
2.6%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Technology Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Hennessy Technology Fund
Class Name Institutional Class
Trading Symbol HTCIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Technology Fund – Institutional Class (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at www.hennessyfunds.com/funds/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website www.hennessyfunds.com/funds/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Institutional Class
$49
0.98%
*Annualized.
Expenses Paid, Amount $ 49
Expense Ratio, Percent 0.98% [59]
Net Assets $ 8,140,718
Holdings Count | Holdings 61
Investment Company, Portfolio Turnover 55.00% [60]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$8,140,718
Number of Portfolio Holdings
61
Annual Portfolio Turnover*
55%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
12.3%
Information Technology
85.1%
Short-Term Investments and Other
2.6%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

Hennessy Sustainable ETF  
Shareholder Report [Line Items]  
Fund Name Hennessy Sustainable ETF
Class Name Hennessy Sustainable ETF
Trading Symbol STNC
Security Exchange Name NASDAQ
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about the Hennessy Sustainable ETF (the “Fund”) for the period of November 1, 2025, to April 30, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at https://www.hennessyetfs.com/etfs/regulatory-documents. You can also request this information by contacting us at 1-800-966-4354 or fundsinfo@hennessyfunds.com.
Additional Information Phone Number 1-800-966-4354
Additional Information Email fundsinfo@hennessyfunds.com
Additional Information Website https://www.hennessyetfs.com/etfs/regulatory-documents
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*
Hennessy Sustainable ETF
$44
0.85%
*Annualized.
Expenses Paid, Amount $ 44
Expense Ratio, Percent 0.85% [61]
Net Assets $ 91,623,140
Holdings Count | Holdings 48
Investment Company, Portfolio Turnover 138.00% [62]
Additional Fund Statistics [Text Block]

Key Fund Statistics

(as of April 30, 2026)

Fund Net Assets
$91,623,140
Number of Portfolio Holdings
48
Annual Portfolio Turnover*
138%
*Not annualized.
Holdings [Text Block]

Sector Breakdown (% of net assets)

sector breakdown
(%)
Communication Services
7.8%
Consumer Discretionary
17.1%
Consumer Staples
8.5%
Financials
6.3%
Health Care
13.7%
Industrials
14.8%
Information Technology
19.8%
Materials
4.1%
Real Estate
2.9%
Utilities
4.8%
Short-Term Investments and Other
0.2%
bar

Sector sub-classifications may differ from those utilized for compliance purposes.

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