Investment Advisory Agreements	9 Months Ended
Jun. 30, 2014
Text Block [Abstract]
Investment Advisory Agreements	(3) Investment Advisory Agreements Effective February 28, 2014, the Hennessy Funds completed an internal reorganization that resulted in all sixteen Hennessy Funds being a series of Hennessy Funds Trust, a Delaware statutory trust. Prior to the reorganization, (i) each of the Hennessy Cornerstone Growth Fund, the Hennessy Cornerstone Mid Cap 30 Fund and the Hennessy Cornerstone Value Fund was a series of Hennessy Mutual Funds, Inc., (ii) each of the Hennessy Total Return Fund and the Hennessy Balanced Fund was a series of The Hennessy Funds, Inc., (iii) each of the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund was a series of Hennessy SPARX Funds Trust and (iv) each of the remaining nine Hennessy Funds was already a series of Hennessy Funds Trust. As a result of the reorganization, the Company now has management contracts only with Hennessy Funds Trust. Pursuant to these management contracts, the Company provides investment advisory services to all classes of the sixteen Hennessy Funds. The management contracts must be renewed annually by (i) the Board of Trustees of Hennessy Funds Trust or by the vote of a majority of the outstanding shares of the applicable Hennessy Fund and (ii) by the vote of a majority of the trustees of Hennessy Funds Trust who are not interested persons of the Hennessy Funds, except that the management contract for the Hennessy Cornerstone Growth Fund, the Hennessy Cornerstone Mid Cap 30 Fund, the Hennessy Cornerstone Value Fund, the Hennessy Total Return Fund, the Hennessy Balanced Fund, the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund has an initial period of two years, which commenced on February 28, 2014, to be renewed annually thereafter. If the management contracts are not renewed as described above, they will terminate automatically. In addition, there are two other circumstances in which the management contracts would terminate. First, the management contracts would automatically terminate if the Company assigned them to another advisor (assignment includes “indirect assignment,” which is the transfer of the Company’s common stock in sufficient quantities deemed to constitute a controlling block). Second, each management contract may be terminated prior to its expiration upon 60 days’ notice by either the Company or the applicable Hennessy Fund. As provided in the management contracts with the sixteen Hennessy Funds, the Company receives investment advisory fees monthly based on a percentage of the respective Hennessy Fund’s average daily net assets. The Company has entered into sub-advisory agreements for the Hennessy Focus Fund, the Hennessy Large Value Fund, the Hennessy Equity and Income Fund, the Hennessy Core Bond Fund, the Hennessy Japan Fund, and the Hennessy Japan Small Cap Fund with the same asset management companies that managed such Hennessy Funds prior to the Company’s purchase of the assets related to the management of such funds. Under each of these sub-advisory agreements, the sub-advisor is responsible for the investment and re-investment of the assets of the applicable Hennessy Fund in accordance with the terms of such agreement and the applicable Hennessy Fund’s Prospectus and Statement of Additional Information. The sub-advisors are subject to the direction, supervision and control of the Company and the Board of Trustees of Hennessy Funds Trust. The sub-advisory agreements must be renewed annually in the same manner and are subject to the same termination provisions as the management contracts, except that the sub-advisory agreement for the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund have an initial period of two years, which commenced on February 28, 2014, to be renewed annually thereafter. In exchange for the sub-advisor services, the Company (not the Hennessy Funds) pays a sub-advisor fee to the sub-advisors, which is based on the amount of each applicable Hennessy Fund’s average daily net assets.

(3) Investment Advisory Agreements

Effective February 28, 2014, the Hennessy Funds completed an internal reorganization that resulted in all sixteen Hennessy Funds being a series of Hennessy Funds Trust, a Delaware statutory trust. Prior to the reorganization, (i) each of the Hennessy Cornerstone Growth Fund, the Hennessy Cornerstone Mid Cap 30 Fund and the Hennessy Cornerstone Value Fund was a series of Hennessy Mutual Funds, Inc., (ii) each of the Hennessy Total Return Fund and the Hennessy Balanced Fund was a series of The Hennessy Funds, Inc., (iii) each of the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund was a series of Hennessy SPARX Funds Trust and (iv) each of the remaining nine Hennessy Funds was already a series of Hennessy Funds Trust. As a result of the reorganization, the Company now has management contracts only with Hennessy Funds Trust. Pursuant to these management contracts, the Company provides investment advisory services to all classes of the sixteen Hennessy Funds.

The management contracts must be renewed annually by (i) the Board of Trustees of Hennessy Funds Trust or by the vote of a majority of the outstanding shares of the applicable Hennessy Fund and (ii) by the vote of a majority of the trustees of Hennessy Funds Trust who are not interested persons of the Hennessy Funds, except that the management contract for the Hennessy Cornerstone Growth Fund, the Hennessy Cornerstone Mid Cap 30 Fund, the Hennessy Cornerstone Value Fund, the Hennessy Total Return Fund, the Hennessy Balanced Fund, the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund has an initial period of two years, which commenced on February 28, 2014, to be renewed annually thereafter. If the management contracts are not renewed as described above, they will terminate automatically. In addition, there are two other circumstances in which the management contracts would terminate. First, the management contracts would automatically terminate if the Company assigned them to another advisor (assignment includes “indirect assignment,” which is the transfer of the Company’s common stock in sufficient quantities deemed to constitute a controlling block). Second, each management contract may be terminated prior to its expiration upon 60 days’ notice by either the Company or the applicable Hennessy Fund.

As provided in the management contracts with the sixteen Hennessy Funds, the Company receives investment advisory fees monthly based on a percentage of the respective Hennessy Fund’s average daily net assets.

The Company has entered into sub-advisory agreements for the Hennessy Focus Fund, the Hennessy Large Value Fund, the Hennessy Equity and Income Fund, the Hennessy Core Bond Fund, the Hennessy Japan Fund, and the Hennessy Japan Small Cap Fund with the same asset management companies that managed such Hennessy Funds prior to the Company’s purchase of the assets related to the management of such funds. Under each of these sub-advisory agreements, the sub-advisor is responsible for the investment and re-investment of the assets of the applicable Hennessy Fund in accordance with the terms of such agreement and the applicable Hennessy Fund’s Prospectus and Statement of Additional Information. The sub-advisors are subject to the direction, supervision and control of the Company and the Board of Trustees of Hennessy Funds Trust. The sub-advisory agreements must be renewed annually in the same manner and are subject to the same termination provisions as the management contracts, except that the sub-advisory agreement for the Hennessy Japan Fund and the Hennessy Japan Small Cap Fund have an initial period of two years, which commenced on February 28, 2014, to be renewed annually thereafter.

In exchange for the sub-advisor services, the Company (not the Hennessy Funds) pays a sub-advisor fee to the sub-advisors, which is based on the amount of each applicable Hennessy Fund’s average daily net assets.