Debt and Warrants - Warrant activity (Details) - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Warrant Activity
Beginning balance	2,427,653	321,314
Warrants granted	2,638,412	2,166,588
Warrants cancelled	(38,570)	(60,249)
Ending balance	5,027,495	2,427,653