Fair Value Measurements - Valuation Technique (Details)	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Derivative Liabilities | Expected dividend yield
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument, Measurement Input	0
Minimum | Warrants | Risk free interest rate
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument, Measurement Input	1.62	2.72
Minimum | Warrants | Volatility
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument, Measurement Input	85.00	75.00
Minimum | Warrants | Expected average term
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument Expected average term	7 years 6 months 4 days	8 years 6 months 4 days
Minimum | Derivative Liabilities | Risk free interest rate
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Measurement Input	1.99	1.64
Minimum | Derivative Liabilities | Volatility
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Measurement Input	22.62	18.40
Minimum | Derivative Liabilities | Expected average term
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Expected average term	11 days	4 days
Maximum | Warrants | Risk free interest rate
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument, Measurement Input	2.33	2.80
Maximum | Warrants | Volatility
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument, Measurement Input		85.00
Maximum | Warrants | Expected average term
Valuation technique for assets and liabilities measured and recorded at fair value
Equity Instrument Expected average term	8 years 3 months 18 days	9 years 3 months 18 days
Maximum | Derivative Liabilities | Risk free interest rate
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Measurement Input	2.51	2.56
Maximum | Derivative Liabilities | Volatility
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Measurement Input	74.93	81.69
Maximum | Derivative Liabilities | Expected average term
Valuation technique for assets and liabilities measured and recorded at fair value
Derivative Liability, Expected average term	6 months 11 days	1 year 6 months 11 days