Fair Value Measurements (Valuation Techniques of Level 3 Liabilities) (Details) - Level 3	Dec. 31, 2020 yr	Dec. 31, 2019 yr
Option pricing model | Stock price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	2.49	4.94
Option pricing model | Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	0.800	0.650
Option pricing model | Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	3.49
Option pricing model | Term | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.59
Option pricing model | Term | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		4.49
Option pricing model | Risk-free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	0.002
Option pricing model | Risk-free rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.016
Option pricing model | Risk-free rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.017
Option pricing model | Change of control probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	0
Option pricing model | Change of control probability | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.050
Option pricing model | Change of control probability | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.100
Option pricing model | Cost of debt
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input	0
Option pricing model | Cost of debt | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.147
Option pricing model | Cost of debt | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants liability, measurement input		0.160
Interest rate reset | Discounted cash flow | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.200	0.250
Interest rate reset | Discounted cash flow | Stock price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	2.49	4.94
Interest rate reset | Discounted cash flow | Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.969	0.741
Interest rate reset | Discounted cash flow | Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	1.04	2.04
Interest rate reset | Discounted cash flow | Risk-free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.001	0.016
Make-whole change of control redemption | Option pricing model | Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0	2.04
Make-whole change of control redemption | Option pricing model | Risk-free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0	0.016
Make-whole change of control redemption | Option pricing model | Change of control probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0
Make-whole change of control redemption | Option pricing model | Change of control probability | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input		0.050
Make-whole change of control redemption | Option pricing model | Change of control probability | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input		0.100
Qualifying change of control redemption derivative liability (2) | Discounted cash flow | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0	0.250
Qualifying change of control redemption derivative liability (2) | Discounted cash flow | Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0	0.60
Qualifying change of control redemption derivative liability (2) | Discounted cash flow | Change of control probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0	0.050
Interest Make-whole Derivative Liability | Discounted cash flow | Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.25	0
Interest Make-whole Derivative Liability | Discounted cash flow | Risk-free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.0010	0
Interest Make-whole Derivative Liability | Discounted cash flow | Recapitalization probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.900	0