Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Prepaid Expenses and Other Assets
Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs	$ 300,000
Vaccinex Products
Summary Of Significant Accounting Policies [Line Items]
Gain or loss from VIE	$ 0	$ 0

Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.A)
-URI http://asc.fasb.org/extlink&oid=27011391&loc=d3e105025-122735

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- Definition

The gain (loss) recognized on initial consolidation of a variable interest entity (VIE) when the VIE is not a business (as defined).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121559654&loc=d3e5710-111685

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- Definition

Line items represent represents lime items of summary of significant accounting policies..

+ References

No definition available.

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