Share-Based Compensation - Summary of Stock Option Activity (Details) - Options - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Options Outstanding
Outstanding at January 1, 2020	14,936,726
Granted	13,750,000
Exercised	(60,000)
Expired	(1,144,326)
Forfeited	(1,153,333)
Outstanding at September 30, 2020	26,329,067	14,936,726
Vested at the end (in shares)	13,684,070
Expected to vest at the end (in shares)	12,644,997
Weighted Average Exercise Price
Outstanding at January 1, 2020	$ 2.13
Granted	0.53
Exercised	1.83
Expired	2.59
Forfeited	1.70
Outstanding at September 30, 2020	1.29	$ 2.13
Vested at the end (in dollars per share)	1.74
Expected to vest at the end (in dollars per share)	$ 0.81
Weighted Average Remaining Contractual Life (Years)
Outstanding at January 1, 2020	8 years 9 months	8 years 5 months 23 days
Granted	9 years 5 months 12 days
Exercised	0 years
Expired	0 years
Forfeited	0 years
Outstanding at September 30, 2020	8 years 9 months	8 years 5 months 23 days
Vested at the end (in years)	8 years 2 months 1 day
Expected to vest at the end (in years)	9 years 4 months 17 days
Aggregated Intrinsic Value
Outstanding at January 1, 2020	$ 5,141,400	$ 0
Granted	5,225,000
Exercised	0
Expired	0
Forfeited	0
Outstanding at September 30, 2020	5,141,400	$ 0
Vested at the end (in dollars)	1,258,592
Expected to vest at the end (in dollars)	$ 3,882,808