Fair Value Measurements - Schedule of Significant Quantitative Level 3 Inputs Utilized (Details) - $ / shares	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock Price Volatility	90.00%
Risk-Free Interest Rate	1.20%	1.00%
Note Conversion Price (USD per share)	$ 0.73	$ 0.73
Discount Rate	26.00%	25.00%
Market Price of Common Stock (USD per share)	$ 2.13	$ 1.58
Compound embedded derivative with the 2013 8.00% Notes \| Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock Price Volatility		100.00%
Compound embedded derivative with the 2013 8.00% Notes \| Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock Price Volatility		110.00%
Compound embedded derivative with the Thermo Loan Agreement
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-Free Interest Rate	2.00%	2.20%
Note Conversion Price (USD per share)	$ 0.73	$ 0.73
Discount Rate	26.00%	25.00%
Market Price of Common Stock (USD per share)	$ 2.13	$ 1.58
Compound embedded derivative with the Thermo Loan Agreement \| Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock Price Volatility	40.00%	40.00%
Compound embedded derivative with the Thermo Loan Agreement \| Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Stock Price Volatility	85.00%	110.00%
Compound embedded derivative with the 2013 8.00% Notes
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Loan interest rate	8.00%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Agreed upon price for the exchange of the underlying asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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Risk-free interest rate assumption used in valuing an instrument.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Price of a single share of a number of saleable stocks of a company.

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