Summary of Significant Accounting Policies - Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Summary of Significant Accounting Policies
Potentially dilutive securities excluded from computation of diluted net loss per share	2,792,135	46,132,068
Series A Convertible Preferred Stock
Summary of Significant Accounting Policies
Potentially dilutive securities excluded from computation of diluted net loss per share		36,196,193
Options
Summary of Significant Accounting Policies
Potentially dilutive securities excluded from computation of diluted net loss per share	825,205	603,291
Warrants | Preferred stock
Summary of Significant Accounting Policies
Potentially dilutive securities excluded from computation of diluted net loss per share		8,725,289
Warrants | Common Stock
Summary of Significant Accounting Policies
Potentially dilutive securities excluded from computation of diluted net loss per share	1,966,930	607,295