Annual report pursuant to Section 13 and 15(d)

Common Stock - Summary of Outstanding Warrants (Detail)

v3.8.0.1
Common Stock - Summary of Outstanding Warrants (Detail)
12 Months Ended
Dec. 31, 2017
$ / shares
shares
Series A Warrants [Member]  
Class of Warrant or Right [Line Items]  
Total Outstanding and Exercisable | shares 252,721
Exercise price per Share | $ / shares $ 44.000
Expiration Date 2019-07
Series B Warrants [Member]  
Class of Warrant or Right [Line Items]  
Total Outstanding and Exercisable | shares 60,933
Exercise price per Share | $ / shares $ 44.000
Expiration Date 2019-07
Series A-1 Warrants [Member]  
Class of Warrant or Right [Line Items]  
Total Outstanding and Exercisable | shares 21,748
Exercise price per Share | $ / shares $ 26.400
Expiration Date 2020-10
Warrants Issued In September 2017 [Member]  
Class of Warrant or Right [Line Items]  
Total Outstanding and Exercisable | shares 82,237
Exercise price per Share | $ / shares $ 3.496
Expiration Date 2023-03