Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Dec. 31, 2021
Entity Registrant Name	Sequoia Fund, Inc.
Entity Central Index Key	0000089043
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Apr. 28, 2022
Document Effective Date	Apr. 29, 2022
Prospectus Date	Apr. 29, 2022
SEQUOIA FUND INC \| SEQUOIA FUND INC
Prospectus:
Trading Symbol	SEQUX

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The date the document was made available and submitted, in YYYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

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The date when a document, upon receipt and acceptance, becomes officially effective, in YYYY-MM-DD format. Usually it is a system-assigned date time value, but it may be declared by the submitter in some cases.

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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One of: N-1A (Mutual Fund), N-1 (Open-End Separate Account with No Variable Annuities), N-2 (Closed-End Investment Company), N-3 (Separate Account Registered as Open-End Management Investment Company), N-4 (Variable Annuity UIT Separate Account), N-5 (Small Business Investment Company), N-6 (Variable Life UIT Separate Account), S-1 or S-3 (Face Amount Certificate Company), S-6 (UIT, Non-Insurance Product).

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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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The date of the prospectus.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Prospectus Table.

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