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Stockholders' Equity - Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions (Details)	Mar. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares	Jul. 25, 2018 $ / shares
Measurement Input, Expected Term
Class Of Stock [Line Items]
Warrants expected term	1 year 9 months 18 days	2 years 1 month 6 days	2 years 6 months
Measurement Input, Share Price
Class Of Stock [Line Items]
Warrants measurement input	13.00	14.50	36.00
Measurement Input, Risk Free Interest Rate
Class Of Stock [Line Items]
Warrants measurement input	0.0238	0.0248	0.0270
Measurement Input, Price Volatility
Class Of Stock [Line Items]
Warrants measurement input	1.28	1.25	1.12
Measurement Input Resulting Fair Value Per Warrant
Class Of Stock [Line Items]
Warrants measurement input	5.00	6.50	22.50

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+ 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=117815213&loc=d3e19207-110258

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
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