v3.19.3.a.u2

Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended			24 Months Ended
	Dec. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 29, 2018
Preferred Stock
Stock issuance costs		$ 0	$ 3,065
Preferred stock, shares authorized (in shares)		10,000,000
Preferred stock, par value (in dollars per share)		$ 0.001
Preferred stock, shares issued (in shares)		0	0
Preferred stock, shares outstanding (in shares)		0	0
Series A preferred stock
Preferred Stock
Convertible preferred stock, shares issued (in shares)					55,500,000
Price per share (in dollars per share)	$ 1.00				$ 1.00
Proceeds from sale of stock					$ 50,900
Stock issuance costs					100
Accrued interest on convertible notes	$ 4,600				$ 4,600
Series B preferred stock \| Subscription Agreement December 2017
Preferred Stock
Convertible preferred stock, shares issued (in shares)	24,911,030
Price per share (in dollars per share)	$ 2.81				$ 2.81
Proceeds from sale of stock	$ 69,700
Stock issuance costs	$ 300
Series B preferred stock \| Subscription Agreement December 2018
Preferred Stock
Convertible preferred stock, shares issued (in shares)				12,811,388
Price per share (in dollars per share)				$ 2.81
Proceeds from sale of stock				$ 35,900
Stock issuance costs				$ 100
Redeemable convertible preferred stock (Series A and B) \| IPO
Preferred Stock
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)						18,644,462

Number of shares issued for each share of convertible preferred stock that is converted.

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Neon Therapeutics, Inc. 10-K