S000001243 [Member] Investment Strategy - LARGE CAP CORE FUND	Mar. 31, 2026
Prospectus [Line Items]
Strategy [Heading]	PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block]	In seeking its investment objective, the Fund will invest, under normal circumstances, at least 80% of its net assets in a broadly diversified portfolio of equity securities of large capitalization U.S. companies, including foreign issuers that are traded in the U.S. Large capitalization companies generally are considered to be those whose market capitalization is within the range of the market capitalization of the companies in the Russell 1000^® Index. The Fund seeks to achieve its investment objective by employing a strategy that uses statistics and advanced econometric methods to evaluate fundamental and quantifiable stock or firm characteristics (such as relative valuation, price momentum and earnings quality). The characteristics are combined to create a proprietary multifactor quantitative stock selection model, which generates stock specific forecasts that are used along with controls intended to manage risk to determine security weightings. Under the Fund’s core investment style, the Fund invests in a mix of both growth and value securities and the Fund’s overall portfolio is not anticipated to show a significant bias to either style. The Fund may use derivatives such as stock index futures contracts to equitize cash and enhance portfolio liquidity. Derivatives instruments that provide investment exposure to investments in the Fund’s 80% investment policy and derivatives instruments that provide investment exposure to one or more of the market risk factors associated with such securities may be counted towards the Fund’s 80% investment policy. NTI will normally sell a security that it believes is no longer attractive based upon the evaluation criteria described above. From time to time the Fund may have a focused investment (i.e., investment exposure comprising more than 15% of its total assets) in one or more particular sectors. As of March 31, 2026, the Fund had a focused investment in the information technology sector. Frank Russell Company does not endorse any of the securities in the Russell 1000^® Index. It is not a sponsor of the Large Cap Core Fund and is not affiliated with the Fund in any way.

In seeking its investment objective, the Fund will invest, under normal circumstances, at least 80% of its net assets in a broadly diversified portfolio of equity securities of large capitalization U.S. companies, including foreign issuers that are traded in the U.S. Large capitalization companies generally are considered to be those whose market capitalization is within the range of the market capitalization of the companies in the Russell 1000^® Index.

The Fund seeks to achieve its investment objective by employing a strategy that uses statistics and advanced econometric methods to evaluate fundamental and quantifiable stock or firm characteristics (such as relative valuation, price momentum and earnings quality). The characteristics are combined to create a proprietary multifactor quantitative stock selection model, which generates stock specific forecasts that are used along with controls intended to manage risk to determine security weightings. Under the Fund’s core investment style, the Fund invests in a mix of both growth and value securities and the Fund’s overall portfolio is not anticipated to show a significant bias to either style.

The Fund may use derivatives such as stock index futures contracts to equitize cash and enhance portfolio liquidity. Derivatives instruments that provide investment exposure to investments in the Fund’s 80% investment policy and derivatives instruments that provide investment exposure to one or more of the market risk factors associated with such securities may be counted towards the Fund’s 80% investment policy. NTI will normally sell a security that it believes is no longer attractive based upon the evaluation criteria described above.

total assets) in one or more particular sectors. As of March 31, 2026, the Fund had a focused investment in the information technology sector.

Frank Russell Company does not endorse any of the securities in the Russell 1000^® Index. It is not a sponsor of the Large Cap Core Fund and is not affiliated with the Fund in any way.