Fair Value Measurements - Schedule of Valuation Assumptions used in Determining Fair Value (Details) - Convertible Debt - 5.00% / 7.00% Second Lien Notes due August 31, 2022 - Level 3	Dec. 31, 2018
Measurement Input, Risk Free Interest Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.0248
Measurement Input, Credit Spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.1896
Measurement Input, Control Premium
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.0200
Measurement Input, Price Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt Instrument, Measurement Input	0.5000