Warrants - Warrant Activity (Details) - Warrant	9 Months Ended
	Sep. 30, 2019 $ / shares shares
Increase (Decrease) in Warrants Outstanding [Roll Forward]
Beginning balance, number of warrants outstanding (shares)	7,392,966
Granted (shares)	0
Exercised (shares)	0
Expired (shares)	0
Ending balance, number of warrants outstanding (shares)	7,392,966
Increase (Decrease) In Weighted-average Exercise Price Of Warrants Outstanding [Roll Forward]
Beginning balance, weighted-average exercise price (usd per share) | $ / shares	$ 7.36
Weighted-average exercise price, warrants granted during the period (usd per share) | $ / shares	0.00
Weighted-average exercise price, warrants exercised during the period (usd per share) | $ / shares	0.00
Weighted-average exercise price, warrants expired during the period (usd per share) | $ / shares	0.00
Ending balance, weighted-average exercise price (usd per share) | $ / shares	$ 7.36
Liability-classified
Increase (Decrease) in Warrants Outstanding [Roll Forward]
Beginning balance, number of warrants outstanding (shares)	1,205,840
Granted (shares)	0
Exercised (shares)	0
Expired (shares)	0
Ending balance, number of warrants outstanding (shares)	1,205,840
Equity-classified
Increase (Decrease) in Warrants Outstanding [Roll Forward]
Beginning balance, number of warrants outstanding (shares)	6,187,126
Granted (shares)	0
Exercised (shares)	0
Expired (shares)	0
Ending balance, number of warrants outstanding (shares)	6,187,126