S000004424 [Member] Expense Example - Ultra-Small Company Market Fund - Class N	Jun. 30, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 77
Expense Example, with Redemption, 3 Years	240
Expense Example, with Redemption, 5 Years	417
Expense Example, with Redemption, 10 Years	$ 930

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Form N-1A
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Form N-1A
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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