Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Fair Value Measurements - Narrative (Details)

v3.8.0.1

Fair Value Measurements - Narrative (Details) $ / shares in Units, shares in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) class_of_stock $ / shares shares	Dec. 31, 2016 USD ($) class_of_stock	Dec. 31, 2015
Level 3 Valuation
Number of changes in valuation techniques \| class_of_stock	0	0
Amount of transfers of assets from level 2 to level 1	$ 0	$ 0
Amount of transfers of assets from level 1 to level 2	$ 0	$ 0
Common stock warrants
Level 3 Valuation
Number of shares available under warrant (in shares) \| shares	40
Minimum
Level 3 Valuation
Expected life	5 years	5 years	5 years
Maximum
Level 3 Valuation
Expected life	6 years 3 months	6 years 3 months	6 years 3 months
Level 2
Level 3 Valuation
Estimated fair value of debt		$ 2,400,000
Level 3
Level 3 Valuation
Change in fair value	$ 29,624	(72,625)
Warrant liability \| Level 3
Level 3 Valuation
Volatility	55.00%
Risk free interest rate	1.96%
Strike price (in dollars per share) \| $ / shares	$ (8.40)
Share price (in dollars per share) \| $ / shares	$ (3.20)
Expected life	2 years 9 months 18 days
Change in fair value	$ 2,684	(22,105)
Equity Unit Purchase Option \| Level 3
Level 3 Valuation
Strike price (in dollars per share) \| $ / shares	$ (7.48)
Change in fair value	$ 26,940	$ (50,520)
Equity Unit Purchase Option \| Level 3 \| Class A Warrant
Level 3 Valuation
Strike price (in dollars per share) \| $ / shares	$ (5.23)
Equity Unit Purchase Option \| Level 3 \| Class B Warrant
Level 3 Valuation
Strike price (in dollars per share) \| $ / shares	$ (4.49)
Equity Unit Purchase Option \| Level 3 \| Minimum
Level 3 Valuation
Volatility	40.00%
Risk free interest rate	1.28%
Equity Unit Purchase Option \| Level 3 \| Maximum
Level 3 Valuation
Volatility	50.00%
Risk free interest rate	2.17%

- Definition

Number of changes in valuation techniques during the period.

+ References

No definition available.

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ 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 (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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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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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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)
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- Definition

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

+ References

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

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- Definition

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

+ References

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-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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- Definition

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.

+ References

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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- Definition

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

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