Shareholders' Equity - Underwritten Public Offering (Details) - Maxim Group, LLC - USD ($)	1 Months Ended	3 Months Ended	5 Months Ended	6 Months Ended	12 Months Ended
	Aug. 31, 2016	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2017	Dec. 31, 2016	Aug. 12, 2016
2016 Underwritten Public Offering
Class of Stock [Line Items]
Proceeds from issuance of common stock and warrants net of offering costs	$ 6,600,000
Common stock issued (in shares)	863,750
2016 Underwritten Public Offering | Warrant
Class of Stock [Line Items]
Warrants to purchase common stock (in shares)	993,115	993,115		993,115
Exercise price of warrants (in USD per share)		$ 0.02		$ 0.02		$ 2.30
2016 Underwritten Public Offering | Base Warrant
Class of Stock [Line Items]
Warrants to purchase common stock (in shares)	881,250
Exercise price of warrants (in USD per share)	$ 7.68
Life of warrants				5 years
Proceeds from issuance of warrants	$ 2,284,395
2016 Underwritten Public Offering | Pre-funded Warrant
Class of Stock [Line Items]
Warrants to purchase common stock (in shares)	311,250
Exercise price of warrants (in USD per share)	$ 0.40
Life of warrants				10 years
Warrants exercised (in shares)		102,500	208,750		208,750
Proceeds from issuance of warrants		$ 41,000	$ 83,500
Over allotment to underwriters
Class of Stock [Line Items]
Common stock issued (in shares)	37,500
Warrants to purchase common stock (in shares)	111,965
Over allotment to underwriters | Common Stock
Class of Stock [Line Items]
Exercise price of warrants (in USD per share)	$ 6.00
Over allotment to underwriters | Warrant
Class of Stock [Line Items]
Exercise price of warrants (in USD per share)	$ 0.40