Annual report pursuant to Section 13 and 15(d)

Stock Compensation (Schedule of Changes in Number of Outstanding Stock Options Under Director Plan, Stock Plan and 2011 Incentive Plan) (Details)

v3.21.1
Stock Compensation (Schedule of Changes in Number of Outstanding Stock Options Under Director Plan, Stock Plan and 2011 Incentive Plan) (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Stock Compensation [Abstract]      
Options, Outstanding - December 31, 1,130,472 1,380,492  
Options, Awarded 191,301 100,769  
Options, Exercised (8,000) (151,950)  
Options, Forfeited (140,583) (198,839)  
Options, Outstanding - December 31, 1,173,190 1,130,472 1,380,492
Options, Exercisable at December 31, 877,926    
Options, Expected to vest December 31, 1,173,190    
Weighted average exercise price per share, Outstanding - December 31, $ 7.28 $ 7.56  
Weighted average exercise price per share, Awarded 5.10 2.69  
Weighted average exercise price per share, Exercised 2.64 4.08  
Weighted average exercise price per share, Forfeited 10.90 9.33  
Weighted average exercise price per share, Outstanding - December 31, 6.52 $ 7.28 $ 7.56
Weighted average exercise price per share, Exercisable at December 31, 7.20    
Weighted average exercise price per share, Expected to vest December 31, $ 6.52    
Options, Outstanding - Weighted average remaining contractual term in years 3 years 4 months 6 days 3 years 5 months 23 days 4 years 2 months 5 days
Options, Exercisable - Weighted average remaining contractual term in years 2 years 7 months 2 days    
Options, Expected to vest - Weighted average remaining contractual term in years 3 years 4 months 6 days