Stock-based Compensation - Summary of Warrant Activity (Details) - $ / shares
9 Months Ended 12 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Warrant Outstanding, Beginning 706,262 111,129 111,129
Warrant Outstanding, Warrants issued   595,133
Warrant Outstanding, Expired  
Warrant Outstanding, Forfeited warrants  
Warrant Outstanding, Exercised 272,727  
Warrant Outstanding, Ending 433,535   706,262
Weighted Average Exercise Price, Beginning $ 3.27 $ 8.25 $ 8.25
Weighted Average Exercise Price, Warrant issued   2.91
Weighted Average Exercise Price, Expired  
Weighted Average Exercise Price, Forfeited warrants  
Weighted Average Exercise Price, Exercised 0.64  
Weighted Average Exercise Price, Ending 5.26   3.27
Weighted Average Fair Value, Beginning 1.48 0.11 0.11
Weighted Average Fair Value, Warrant issued $ 1.74 1.74
Weighted Average Fair Value, Expired  
Weighted Average Fair Value, Forfeited warrants  
Weighted Average Fair Value, Exercised 0.54  
Weighted Average Fair Value, Ending $ 2.08   $ 1.48
Weighted-average Remaining Contractual Life (Years), Beginning 4 years 2 months 19 days   4 years 10 months 28 days
Weighted-average Remaining Contractual Life (Years), Warrants issued 3 years 7 months 21 days   4 years 3 months 11 days
Weighted-average Remaining Contractual Life (Years), Ending 3 years 4 months 13 days   4 years 2 months 19 days