Quarterly report pursuant to Section 13 or 15(d)

Equity Incentive Plan (Details)

v3.10.0.1
Equity Incentive Plan (Details)
9 Months Ended
Nov. 01, 2017
Sep. 30, 2018
$ / shares
shares
Sep. 30, 2017
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of restricted common shares reserved for issuance under equity incentive plan (in shares)   6,500,000  
Reverse stock split, conversion ratio 0.50    
Number of restricted common shares granted during period under equity incentive plan (in shares)   996,924 671,845
Weighted average grant date fair value of restricted common shares granted during period under equity incentive plan (in usd per share) | $ / shares   $ 14.96 $ 17.60
Director [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of restricted common shares granted during period under equity incentive plan (in shares)   55,553 34,559
Weighted average grant date fair value of restricted common shares granted during period under equity incentive plan (in usd per share) | $ / shares   $ 15.48 $ 19.82
Key Employees [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of restricted common shares granted during period under equity incentive plan (in shares)   941,371 637,286
Weighted average grant date fair value of restricted common shares granted during period under equity incentive plan (in usd per share) | $ / shares   $ 15.12 $ 17.48
Award vesting period of restricted common shares granted during period under equity incentive plan   3 years