Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Schedule of Assumptions Used in Estimating Fair Value (Details)

v3.19.1
Fair Value Measurements - Schedule of Assumptions Used in Estimating Fair Value (Details) - Common Stock Warrants [Member]
3 Months Ended 12 Months Ended
Mar. 31, 2019
Dec. 31, 2018
Black-Scholes-Merton Valuation Model [Member] | Weighted-Average Risk-Free Interest Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 2.23% 2.51%
Black-Scholes-Merton Valuation Model [Member] | Weighted-Average Expected Life [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, term 4 years 1 month 9 days 10 months 25 days
Black-Scholes-Merton Valuation Model [Member] | Expected Dividend Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 0.00% 0.00%
Black-Scholes-Merton Valuation Model [Member] | Weighted-Average Expected Volatility [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 68.00% 157.00%
Monte Carlo Simulation Valuation Model [Member] | Weighted-Average Risk-Free Interest Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 2.42% 2.46%
Monte Carlo Simulation Valuation Model [Member] | Weighted-Average Expected Life [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, term 2 years 7 months 28 days 3 years 1 month 6 days
Monte Carlo Simulation Valuation Model [Member] | Expected Dividend Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 0.00% 0.00%
Monte Carlo Simulation Valuation Model [Member] | Weighted-Average Expected Volatility [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value assumptions, measurement input, percentages 68.00% 68.00%