Nature of Business	9 Months Ended
Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	1. Nature of Business Syndax Pharmaceuticals, Inc., is a clinical stage biopharmaceutical company developing an innovative pipeline of cancer therapies. We were incorporated in Delaware in 2005. We base our operations in Waltham, Massachusetts and we operate in one segment. References in these notes to condensed consolidated financial statements to “Syndax,” “the Company,” “we,” “us” or “our” refer to Syndax Pharmaceuticals, Inc. and its wholly owned subsidiaries.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org//275/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482861/275-10-50-1

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