Stock-Based Compensation - Summary of Restricted Stock Unit (RSU) Activity (Details) - Restricted Stock Units (RSUs)	9 Months Ended
	Sep. 30, 2019 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding, number of awards (in shares) | shares	35,000
Awarded, number of awards (in shares) | shares	526,500
Vested and released (in shares) | shares	(74,000)
Outstanding, number of awards (in shares) | shares	488,000
Outstanding, weighted average grant date fair value per share (in dollars per share) | $ / shares	$ 12.43
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares	0.75
Vested and released, weighted average grant date fair value per share (in dollars per share) | $ / shares	6.51
Outstanding, weighted average grant date fair value per share (in dollars per share) | $ / shares	$ 0.74