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Stockholders' Equity - Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions (Details)	Sep. 30, 2019 $ / shares	Sep. 25, 2019 $ / shares	Dec. 31, 2018 $ / shares
Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants expected term	5 years
Expected Term [Member]
Class Of Stock [Line Items]
Warrants expected term	1 year 7 months 6 days		2 years 1 month 6 days
Expected Term [Member] | Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants expected term	5 years	5 years
Common Stock Market Price [Member]
Class Of Stock [Line Items]
Warrants measurement input	3.42		14.50
Common Stock Market Price [Member] | Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants measurement input	3.42	3.42
Risk-free Interest Rate [Member]
Class Of Stock [Line Items]
Warrants measurement input	0.0170		0.0248
Risk-free Interest Rate [Member] | Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants measurement input	0.0155	0.0160
Expected Volatility [Member]
Class Of Stock [Line Items]
Warrants measurement input	1.76		1.25
Expected Volatility [Member] | Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants measurement input	1.349	1.349
Resulting Fair Value (Per Warrant) [Member]
Class Of Stock [Line Items]
Warrants measurement input	2.53		0.13
Resulting Fair Value (Per Warrant) [Member] | Series U Warrants [Member]
Class Of Stock [Line Items]
Warrants measurement input	2.90	2.90

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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
-Paragraph 2
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