Share-Based Compensation - Option Price Ranges (Details) - $ / shares
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Options Outstanding, Number Outstanding (in shares) 219,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 2 years 9 months 18 days 2 years 6 months 25 days 2 years 7 months 6 days 3 years 18 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 42.38      
Options Exercisable, Number of Shares 114,000      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 47.43      
$30.40 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 30.4      
Shares authorized under stock option plans, exercise price range, upper range limit $ 30.4      
Options Outstanding, Number Outstanding (in shares) 42,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 11 months 8 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 5.83      
Options Exercisable, Number of Shares 0      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 0      
$35.70 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 35.7      
Shares authorized under stock option plans, exercise price range, upper range limit $ 35.7      
Options Outstanding, Number Outstanding (in shares) 36,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 7 months 24 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 5.87      
Options Exercisable, Number of Shares 9,000      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 2.82      
$41.60 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 41.6      
Shares authorized under stock option plans, exercise price range, upper range limit $ 41.6      
Options Outstanding, Number Outstanding (in shares) 36,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 5 months 12 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 6.84      
Options Exercisable, Number of Shares 20,250      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 7.39      
$42.56 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 42.56      
Shares authorized under stock option plans, exercise price range, upper range limit $ 42.56      
Options Outstanding, Number Outstanding (in shares) 36,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 3 months 29 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 6.99      
Options Exercisable, Number of Shares 27,000      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 10.08      
$52.92 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 52.92      
Shares authorized under stock option plans, exercise price range, upper range limit $ 52.92      
Options Outstanding, Number Outstanding (in shares) 30,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 3 months 29 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 7.25      
Options Exercisable, Number of Shares 18,750      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 8.70      
$53.90 Exercise Price Range        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Shares authorized under stock option plans, exercise price range, lower range limit 53.9      
Shares authorized under stock option plans, exercise price range, upper range limit $ 53.9      
Options Outstanding, Number Outstanding (in shares) 39,000      
Options Outstanding, Weighted-Average Remaining Contractual Life (Years) 1 month 2 days      
Options Outstanding, Weighted-Average Exercise Price (in dollars per share) $ 9.60      
Options Exercisable, Number of Shares 39,000      
Options Exercisable, Weighted-Average Exercise Price (in dollars per share) $ 18.44