Stockholders' Equity - Summary of Warrant Activity (Details) - Warrants	12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares
Class Of Warrant Or Right [Line Items]
Number of Shares, Outstanding at end of period | shares	317,630
Number of Shares, Expired | shares	(317,630)
Number of Shares, Outstanding at end of period | shares	0
Weighted Average Exercise Price, Warrants
Weighted Average Exercise Price, Outstanding at beginning of period | $ / shares	$ 123.61
Weighted Average Exercise Price, Expired | $ / shares	0
Weighted Average Exercise Price, Outstanding at end of period | $ / shares	$ 0
Weighted Average Remaining Contract Term, Warrants
Weighted Average Remaining Contract Term, Exercisable at beginning of period	3 months 14 days
Intrinsic Value, Warrants
Intrinsic Value, Outstanding at beginning of period | $	$ 0
Intrinsic Value, Expired | $	0
Intrinsic Value, Exercisable at end of period | $	$ 0