Fair Value - Fair value of warrant liability (Details) - Level 3 - Valuation Technique, Option Pricing Model	Nov. 30, 2020
Expected volatility | Warrant Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	41.87
Expected volatility | Contingent Value Rights Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	59.74
Risk free interest rates | Warrant Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	0.18
Risk free interest rates | Contingent Value Rights Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	0.10
Expected term (in years) | Warrant Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	2.7
Expected term (in years) | Contingent Value Rights Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	0.7
Annual dividend yield | Warrant Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	1.03
Annual dividend yield | Contingent Value Rights Liability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average significant input for fair value measurement	1.7