Quarterly report pursuant to Section 13 or 15(d)

Stock-based compensation - Summary of Status of Company's Restricted Stock Option Activity (Details)

v3.7.0.1
Stock-based compensation - Summary of Status of Company's Restricted Stock Option Activity (Details)
 3 Months Ended
Mar. 31, 2017
$ / shares
shares
Shares  
Beginning balance (in shares) 1,857,012
Granted (in shares) 0
Cancelled, expired, or forfeited (in shares) (207,500)
Ending balance (in shares) 1,649,512
Exercisable at end of period (in shares) 873,341
Weighted Average Exercise Price  
Beginning balance (in dollars per share) | $ / shares $ 4.28
Granted (in dollars per share) | $ / shares 0.00
Cancelled, expired, or forfeited (in dollars per share) | $ / shares 3.43
Ending balance (in dollars per share) | $ / shares $ 4.39
Restricted Stock  
Shares  
Beginning balance (in shares) 716,250
Granted (in shares) 0
Cancelled, expired, or forfeited (in shares) (7,500)
Ending balance (in shares) 708,750
Exercisable at end of period (in shares) 0
Weighted Average Exercise Price  
Beginning balance (in dollars per share) | $ / shares $ 2.73
Granted (in dollars per share) | $ / shares 0.00
Cancelled, expired, or forfeited (in dollars per share) | $ / shares 2.73
Ending balance (in dollars per share) | $ / shares $ 2.73