Equity Incentive Plan Equity Incentive Plan (Tables)
 9 Months Ended
Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
The following table summarizes the activity related to restricted common stock for the nine months ended September 30, 2016 and 2015:
 
Nine Months Ended September 30,
 
2016
 
2015
(in thousands)
Shares
 
Weighted Average Grant Date Fair Market Value
 
Shares
 
Weighted Average Grant Date Fair Market Value
Outstanding at Beginning of Period
2,290,609

 
$
10.36

 
2,002,406

 
$
10.32

Granted
2,019,261

 
7.56

 
1,170,803

 
10.48

Vested
(1,209,116
)
 
(10.10
)
 
(730,832
)
 
(10.45
)
Forfeited
(301,217
)
 
(8.50
)
 
(61,159
)
 
(10.17
)
Outstanding at End of Period
2,799,537

 
$
8.65

 
2,381,218

 
$
10.36