Annual report pursuant to Section 13 and 15(d)

Stock Plans and Management Compensation (Details 1)

v3.20.4
Stock Plans and Management Compensation (Details 1) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Shares Available for Grant (in shares) 4,900    
Non-Vested Stock Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee   62 years  
Share-Based Compensation Expense $ 13,300 $ 10,900 $ 11,100
Share-Based Compensation Expense, Tax Benefit 3,300 2,700 2,800
Fair Value of Shares Vested During the Period $ 6,600 $ 19,200 $ 4,400
Weighted Average Grant Date Fair Value $ 57.31 $ 53.42  
Awarded - Weighted Average Grant Date Fair Value 64.13 $ 49.12 $ 59.05
Forfeited - Weighted Average Grant Date Fair Value 57.72    
Vested - Weighted Average Grant Date Fair Value $ 58.58    
Share-Based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]      
Outstanding at January 1 444    
Awarded 272    
Forfeited (58)    
Vested (87)    
Outstanding at December 31 571 444  
Unrecognized Compensation Cost $ 11,000    
Non-Vested Stock Awards [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee plus Grantees Total Number of Years of Service 70 years    
Stock Options and SAR's [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee   62 years  
SARs/Stock Options Outstanding [Roll Forward]      
Outstanding on January 1 119 343 594
Exercised (97) (224) (248)
Forfeited 0 0 (3)
Outstanding on December 31 22 119 343
Exercisable and Vested on December 31 22 119 343
Weighted Average Exercise Price [Abstract]      
Outstanding on January 1 $ 21.57 $ 16.04 $ 14.40
Exercised 21.16 13.13 12.10
Forfeited 11.08 5.86 17.06
Outstanding on December 31 23.41 21.57 16.04
Exercisable and Vested on December 31 $ 23.41 $ 21.57 $ 16.04
Aggregate Intrinsic Value [Abstract]      
Exercised $ 5,353 $ 10,494 $ 12,636
Outstanding on December 31 6,276 4,571 10,439
Exercisable and Vested on December 31 $ 6,276 4,571 10,439
Stock Options and SAR's [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee plus Grantees Total Number of Years of Service 70 years    
Performance Shares [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-Based Compensation Expense $ 13,800 6,400 5,600
Share-Based Compensation Expense, Tax Benefit 3,400 1,600 1,400
Fair Value of Shares Vested During the Period $ 3,400 $ 4,900 $ 7,800
Weighted Average Grant Date Fair Value $ 55.71 $ 53.55  
Awarded - Weighted Average Grant Date Fair Value 63.13    
Forfeited - Weighted Average Grant Date Fair Value 57.71    
Vested - Weighted Average Grant Date Fair Value $ 42.34    
Share-Based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]      
Outstanding at January 1 88    
Awarded 116    
Forfeited (37)    
Vested (45)    
Outstanding at December 31 212 88  
Unrecognized Compensation Cost $ 4,000