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Subsequent Events - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands							3 Months Ended
	Aug. 07, 2020	Aug. 03, 2020	Jul. 30, 2020	Jul. 29, 2020	Jul. 09, 2020	Jul. 01, 2020	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Subsequent Event [Line Items]
Common stock, par value							$ 0.0001	$ 0.0001		$ 0.0001
Keystone Capital Partners, LLC
Subsequent Event [Line Items]
Common stock, par value									$ 4.00
Subsequent Event
Subsequent Event [Line Items]
Debenture redemption percentage		115.00%
Percentage of funds used to redeem outstanding debentures		20.00%
Common Stock
Subsequent Event [Line Items]
Exchange of units for common shares							4,125	4,455
Common Stock \| Subsequent Event \| Vaccinex Products, LP Units
Subsequent Event [Line Items]
Exchange of units for common shares	12,377
Common stock, par value	$ 0.0001
Open Market Sale Agreement
Subsequent Event [Line Items]
Proceeds from the sale of shares							$ 1,200
Open Market Sale Agreement \| Common Stock
Subsequent Event [Line Items]
Number of common stock sold							317,688
Open Market Sale Agreement \| Common Stock \| Subsequent Event
Subsequent Event [Line Items]
Number of common stock sold						1,886,590
Number of common stock sold, per share						$ 3.80
Proceeds from the sale of shares						$ 6,900
Stock Purchase Agreement \| Keystone Capital Partners, LLC
Subsequent Event [Line Items]
Proceeds from the sale of shares							$ 1,100
Stock Purchase Agreement \| Subsequent Event \| Keystone Capital Partners, LLC
Subsequent Event [Line Items]
Proceeds from the sale of shares				$ 300
Stock Purchase Agreement \| Common Stock \| Keystone Capital Partners, LLC
Subsequent Event [Line Items]
Number of common stock sold							324,424
Stock Purchase Agreement \| Common Stock \| Subsequent Event
Subsequent Event [Line Items]
Proceeds from the sale of shares					$ 4,000
Stock Purchase Agreement \| Common Stock \| Subsequent Event \| Keystone Capital Partners, LLC
Subsequent Event [Line Items]
Number of common stock sold				47,319
Securities Purchase Agreement \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument principal amount			$ 8,640
Debt instrument interest rate		7.00%	7.00%
Purchase price of convertible debentures			$ 8,000
Debt instrument, discount rate			8.00%
Debenture maturity date		Aug. 03, 2021
Common stock conversion price		$ 9.4125