Fair Value Measurements - Estimated Fair Value of Warrant Liability (Details)		1 Months Ended	2 Months Ended	3 Months Ended		4 Months Ended	9 Months Ended
	Mar. 31, 2019 USD ($) item	Jun. 26, 2019 USD ($) item	May 31, 2019 item	Sep. 30, 2019 USD ($) Y item $ / shares	Jun. 26, 2019 USD ($) item	Jun. 30, 2019 USD ($) item	Sep. 30, 2019 USD ($) Y item $ / shares	Jul. 31, 2019 USD ($)	Jul. 23, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Feb. 28, 2015 USD ($)
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				$ 493,688			$ 493,688
Principal amount											$ 150,000
Exercise price (in dollars per share) | $ / shares				$ 49.00			$ 49.00
Strike price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability | $ / shares				58.80			58.80
Expected life
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability | Y				5			5
Volatility
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				132			132
Risk free rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				2.77			2.77
Dividend rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0			0
Series A Warrants | Stock price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0131			0.0131			0.1610
Series A Warrants | Strike price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				7.8750			7.8750			7.8750
Series A Warrants | Expected life
Fair Value Assumptions and Methodology for Assets and Liabilities
Weighted-average expected term (years)				2 years 7 months 28 days			2 years 7 months 28 days			3 years 4 months 28 days
Series A Warrants | Volatility
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				1.4431			1.4431			1.3563
Series A Warrants | Risk free rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0156			0.0156			0.0246
Underwriter Warrants | Stock price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0131			0.0131			0.1610
Underwriter Warrants | Strike price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.5250			0.5250			0.5250
Underwriter Warrants | Expected life
Fair Value Assumptions and Methodology for Assets and Liabilities
Weighted-average expected term (years)				4 years 4 days			4 years 4 days			4 years 9 months 4 days
Underwriter Warrants | Volatility
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				1.4431			1.4431			1.3563
Underwriter Warrants | Risk free rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0155			0.0155			0.0251
LOC Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Change in fair value of liability				$ 79,891			$ 45,218
LOC Warrants | Stock price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability | item	0.1960			0.0173			0.0173
LOC Warrants | Strike price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability | item	0.1750			0.0200			0.0200
LOC Warrants | Expected life
Fair Value Assumptions and Methodology for Assets and Liabilities
Weighted-average expected term (years)	5 years			5 years			5 years
LOC Warrants | Volatility
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability	1.4572			1.4743			1.4743
LOC Warrants | Risk free rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability	0.0223			0.0183			0.0183
2019 Bridge Note Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant						$ 4,259,327		$ 5,005,739	$ 4,259,327
Change in fair value of liability				$ 718,654			$ 747,300
Principal amount		$ 5,050,000			$ 5,050,000
Number of promissory notes issued | item	21	21	21
Term of promissory notes						4 months
2019 Bridge Note Warrants | Stock price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0173			0.0173
2019 Bridge Note Warrants | Stock price | Minimum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.0484
2019 Bridge Note Warrants | Stock price | Maximum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.3290
2019 Bridge Note Warrants | Strike price
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0200			0.0200
2019 Bridge Note Warrants | Strike price | Minimum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.0484
2019 Bridge Note Warrants | Strike price | Maximum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.3290
2019 Bridge Note Warrants | Expected life
Fair Value Assumptions and Methodology for Assets and Liabilities
Weighted-average expected term (years)				4 years 9 months 18 days			4 years 9 months 18 days	5 years
2019 Bridge Note Warrants | Volatility
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				1.4584			1.4584
2019 Bridge Note Warrants | Volatility | Minimum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								1.4560
2019 Bridge Note Warrants | Volatility | Maximum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								1.4572
2019 Bridge Note Warrants | Risk free rate
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability				0.0176			0.0176
2019 Bridge Note Warrants | Risk free rate | Minimum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.0176
2019 Bridge Note Warrants | Risk free rate | Maximum
Fair Value Assumptions and Methodology for Assets and Liabilities
Warrant liability								0.0223
Warrant liability | Recurring | Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				$ 10,029			$ 10,029			$ 220,376
Change in fair value of liability							(1,002,865)
Warrant liability | Series A Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				49			49			7,388
Change in fair value of liability				1,004			7,339
Warrant liability | Series A Warrants | Recurring | Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				49			49			7,388
Warrant liability | Underwriter Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				9,980			9,980			212,988
Warrant liability | Underwriter Warrants | Recurring | Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				9,980			9,980			$ 212,988
Change in fair value of liability				42,285			203,008
Warrant liability | LOC Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant	$ 116,297
Warrant liability | LOC Warrants | Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				71,079			71,079
Warrant liability | LOC Warrants | Recurring | Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				0			0
Warrant liability | 2019 Bridge Note Warrants | Recurring
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant				$ 0			$ 0
2019 Bridge Notes
Fair Value Assumptions and Methodology for Assets and Liabilities
Fair value of warrant		$ 5,005,739			$ 5,005,739
Principal amount						$ 5,050,000
Number of promissory notes issued | item					21	21
Fourteen Promissory Notes [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities
Principal amount		3,550,000			$ 3,550,000	$ 3,550,000
Number of promissory notes issued | item					14	14
Warrant coverage percentage					125.00%	125.00%
Seven Promissory Notes [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities
Principal amount		$ 1,500,000			$ 1,500,000	$ 1,500,000
Number of promissory notes issued | item					7	7
Warrant coverage percentage					75.00%	75.00%
Twenty One Promissory Notes [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities
Number of promissory notes issued | item						21
Twenty One Promissory Notes [Member] | 2019 Bridge Note Warrants
Fair Value Assumptions and Methodology for Assets and Liabilities
Exercise price (in dollars per share) | $ / shares									$ 2.00