Contractual interest rate for funds borrowed, under the debt agreement.

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Fair Value Measurements - Derivative Liabilities (Details)	Sep. 30, 2020 $ / shares	Feb. 19, 2020 $ / shares	Dec. 31, 2019 $ / shares
Stock Price Volatility \| Compound embedded derivative with the 2013 8.00% Notes \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.50		0.70
Stock Price Volatility \| Compound embedded derivative with the 2013 8.00% Notes \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.92		1.30
Stock Price Volatility \| Compound embedded derivative with the Loan Agreement with Thermo \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			0.70
Stock Price Volatility \| Compound embedded derivative with the Loan Agreement with Thermo \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			1.30
Risk-Free Interest Rate \| Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.002		0.016
Measurement input		0.014
Risk-Free Interest Rate \| Compound embedded derivative with the Loan Agreement with Thermo
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			0.016
Note Conversion Price \| Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.69		0.69
Measurement input		0.69
Note Conversion Price \| Compound embedded derivative with the Loan Agreement with Thermo
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			0.69
Discount Rate \| Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.23		0.27
Measurement input		0.27
Discount Rate \| Compound embedded derivative with the Loan Agreement with Thermo
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			0.27
Market Price of Common Stock \| Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.31		0.52
Measurement input		0.42
Market Price of Common Stock \| Compound embedded derivative with the Loan Agreement with Thermo
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input			0.52
Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan interest rate, percentage	8.00%		8.00%