Derivative Warrants - Schedule of Assumptions Used (Details)	Mar. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares	Aug. 07, 2017 $ / shares
Class of Warrant or Right [Line Items]
Exercise price of warrants (in USD per warrant)	$ 39.82	$ 39.82	$ 39.82
Closing stock price (in USD per share)	$ 8.90	$ 8.20
Risk free rate
Class of Warrant or Right [Line Items]
Measurement input	0.0222	0.0251
Expected volatility
Class of Warrant or Right [Line Items]
Measurement input	0.4330	0.3687

Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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

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

+ References

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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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