Warrants (Details) - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 0.00
Number of warrants outstanding	11,817,912
Warrants exercised via cashless exercises	0	0
Class of Warrants Issued January 11, 2017
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 0.001
Number of warrants outstanding	7,258,263
November 20, 2017 Warrants
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 0.001
Number of warrants outstanding	4,137,999
Class of Warrants Issued June 11, 2018
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 0.001
Number of warrants outstanding	421,650