Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2016

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

The following reconciliation represents the change in fair value of the embedded conversion feature of the New Convertible Notes between December 31, 2015 and June 30, 2016:

	Derivative liability for embedded conversion feature
Fair value as of December 31, 2015	$	—
Fair value at issuance date	11,574
Settlement upon conversion into common stock	(721		)
Mark-to-market adjustment on conversion feature(a)	(1,284		)
Fair value as of June 30, 2016	$	9,569

Measurement of assets and liabilities at fair value on a recurring basis

The liabilities measured at fair value on a recurring basis were as follows:

	Level 1		Level 2		Level 3		Total(a)
As of June 30, 2016
Derivative liability for commodity hedges	$	—	$	417	$	—	$	417
As of December 31, 2015
Derivative liability for commodity hedges	$	—	$	1,015	$	—	$	1,015

Convertible Notes Due in 2019 [Member]

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Inputs, Liabilities, Quantitative Information [Table Text Block]

The main inputs and assumptions into the fair value model for the New Convertible Notes at June 30, 2016 were as follows:

Company's stock price at the end of the period	$	1.64
Expected volatility	71.00		%
Credit spreads	48.16		%
Risk-free interest rate	0.79		%