S000012102 [Member] Investment Strategy - S000012102 [Member]	Apr. 30, 2025
Prospectus [Line Items]
Strategy [Heading]	Principal Investment Strategies
Strategy Narrative [Text Block]	Under normal circumstances, the Fund invests at least 80% of its net assets (including the amount of any borrowings for investment purposes) in equity securities of companies that have market capitalizations in the range of the companies in the Russell 2000® Value Index (the Index) at the time of purchase (between $48.7 million and $11.2 billion as of July 31, 2025), that the Fund’s investment manager believes are undervalued. The market capitalization range and composition of companies in the Index are subject to change. The Fund may invest up to 20% of its total assets in foreign securities. The Fund also may invest up to 20% of its total assets in real estate investment trusts. The Fund may at times emphasize one or more sectors in selecting its investments, including the financials sector.

S000012102 [Member] Investment Strategy - S000012102 [Member]

Apr. 30, 2025

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets (including the amount of any borrowings for investment purposes) in equity securities of companies that have market capitalizations in the range of the companies in the Russell 2000® Value Index (the Index) at the time of purchase (between $48.7 million and $11.2 billion as of July 31, 2025), that the Fund’s investment manager believes are undervalued. The market capitalization range and composition of companies in the Index are subject to change.

The Fund may invest up to 20% of its total assets in foreign securities. The Fund also may invest up to 20% of its total assets in real estate investment trusts. The Fund may at times emphasize one or more sectors in selecting its investments, including the financials sector.