Common Stock Warrant Liabilities (Tables)

12 Months Ended

Dec. 31, 2019

Warrants and Rights Note Disclosure [Abstract]

Convertible Common Stock Warrant Liabilities

The fair value of the warrants as of May 17, 2019 was estimated using the following assumptions:

	Series B			Series C			Series D			Series F			Total
Fair value (in thousands)	$	1,818		$	792		$	668		$	2,387		$	5,665
Expected remaining term (in years)	4.46			5.47			7.21			9.62
Risk-free interest rate	2.17		%	2.20		%	2.27		%	2.37		%
Expected volatility	39.0		%	39.3		%	40.2		%	42.4		%
Dividend yield	—			—			—			—

The fair value of the warrants as of December 31, 2018 was estimated using the following assumptions:

	Series B			Series C			Series D			Series F			Total
Fair value (in thousands)	$	857		$	407		$	358		$	1,639		$	3,261
Expected remaining term (in years)	4.84			5.84			7.59			10.00
Risk-free interest rate	2.62		%	2.62		%	2.62		%	2.80		%
Expected volatility	50.0		%	50.0		%	50.0		%	50.0		%
Dividend yield	—			—			—			—