Expense Example - SEQUOIA FUND INC - SEQUOIA FUND INC	Apr. 27, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 113
Expense Example, with Redemption, 3 Years	353
Expense Example, with Redemption, 5 Years	612
Expense Example, with Redemption, 10 Years	$ 1,352

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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