Warrants - Schedule Of Fair Value Measurement Inputs and Valuation Techniques Used In Determining Warrant Liability (Detail)	Sep. 30, 2020 yr	Dec. 31, 2019 yr
Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0
Volatility | Maximum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	89.50	123.64
Volatility | Minimum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	85.36	117.43
Remaining Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0
Remaining Term | Maximum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	4.64	4.86
Remaining Term | Minimum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	2.03	2.78
Risk Free Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0
Risk Free Rate | Maximum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.34	1.69
Risk Free Rate | Minimum [Member] | Liability Classified Warrant [member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.25	1.68