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Summary of Significant Accounting Policies - 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
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [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
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants measurement input	13.00	14.50	36.00
Measurement Input, Risk Free Interest Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants measurement input	0.0238	0.0248	0.0270
Measurement Input, Price Volatility
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants measurement input	1.28	1.25	1.12
Measurement Input Resulting Fair Value Per Warrant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants measurement input	5.00	6.50	22.50

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+ 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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+ References

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