Quarterly report pursuant to Section 13 or 15(d)

Stock options and warrants (Schedule of Award Activity) (Details)

v3.4.0.3
Stock options and warrants (Schedule of Award Activity) (Details) - USD ($)
3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Stock Incentive Plan [Member]    
Shares Underlying Options    
Outstanding, beginning 332,560  
Granted
Exercised
Forfeited (7,382) (21,668)
Outstanding, ending 325,178  
Exercisable 305,265  
Weighted Average Exercise Price    
Outstanding, beginning $ 35.36  
Granted  
Exercised  
Forfeited $ 20.98  
Outstanding, ending 35.75  
Exercisable $ 37.10  
Weighted Average Remaining Contractual Term    
Outstanding 7 years 6 months  
Outstanding and exercisable 7 years 6 months  
Aggregate Intrinsic Value    
Outstanding  
Exercisable  
Nonqualified [Member]    
Shares Underlying Options    
Outstanding, beginning 432,003  
Granted  
Exercised  
Forfeited  
Outstanding, ending 432,003  
Weighted Average Exercise Price    
Outstanding, beginning $ 15.47  
Granted  
Exercised  
Forfeited  
Outstanding, ending $ 15.47  
Weighted Average Remaining Contractual Term    
Outstanding 2 years  
Aggregate Intrinsic Value    
Outstanding  
Exercisable