S000043215 [Member] Investment Strategy - AB Concentrated Growth Fund	Jun. 30, 2026
Prospectus [Line Items]
Strategy [Heading]	PRINCIPAL STRATEGIES
Strategy Narrative [Text Block]	The Adviser seeks to achieve the Fund’s investment objective of long-term growth of capital by investing primarily in common stocks of listed U.S. companies. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in common stocks of listed companies meeting the Adviser’s growth criteria. For purposes of this policy, companies meeting the Adviser’s growth criteria are those companies with securities included in any one of the following indexes: the MSCI ACWI IMI Growth, the Russell 3000^® Growth Index, and the Morningstar Global All‑Cap Growth TME. The Adviser employs an appraisal method that attempts to measure each prospective company’s quality and growth rate by numerous factors. Such factors include: a company’s record and projections of profit and earnings growth, accuracy and availability of information with respect to the company, success and experience of management, accessibility of management to the Fund’s Adviser, product lines and competitive position both in the United States and abroad, lack of cyclicality, large market capitalization and liquidity of the company’s securities. The Adviser compares these results to the general stock markets to determine the relative attractiveness of each company at a given time. The Adviser weighs economic, political and market factors in making investment decisions; this appraisal technique attempts to measure each investment candidate not only against other stocks of the same industry group, but also against a broad spectrum of investments. While the Fund primarily invests in companies that have market capitalizations of $5 billion or more, it may invest in companies that have market capitalizations of $3 billion to $5 billion. The Fund invests in a relatively small number of individual stocks. The Fund is considered to be “non‑diversified”, which means that the securities laws do not limit the percentage of its assets that it may invest in any one company (subject to certain limitations under the U.S. Internal Revenue Code of 1986, as amended).

The Adviser seeks to achieve the Fund’s investment objective of long-term growth of capital by investing primarily in common stocks of listed U.S. companies. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in common stocks of listed companies meeting the Adviser’s growth criteria. For purposes of this policy, companies meeting the Adviser’s growth criteria are those companies with securities included in any one of the following indexes: the MSCI ACWI IMI Growth, the Russell 3000^® Growth Index, and the Morningstar Global All‑Cap Growth TME.

The Adviser employs an appraisal method that attempts to measure each prospective company’s quality and growth rate by numerous factors. Such factors include: a company’s record and projections of profit and earnings growth, accuracy and availability of information with respect to the company, success and experience of management, accessibility of management to the Fund’s Adviser, product lines and competitive position both in the United States and abroad, lack of cyclicality, large market capitalization and liquidity of the company’s securities. The Adviser compares these results to the general stock markets to determine the relative attractiveness of each company at a given time. The Adviser weighs economic, political and market factors in making investment decisions; this appraisal technique attempts to measure each investment candidate not only against other stocks of the same industry group, but also against a broad spectrum of investments. While the Fund primarily invests in companies that have market capitalizations of $5 billion or more, it may invest in companies that have market capitalizations of $3 billion to $5 billion.

The Fund invests in a relatively small number of individual stocks. The Fund is considered to be “non‑diversified”, which means that the securities laws do not limit the percentage of its assets that it may invest in any one company (subject to certain limitations under the U.S. Internal Revenue Code of 1986, as amended).