XML 164 R135.htm IDEA: XBRL DOCUMENT v3.20.4
Stock Based Compensation (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Excess Tax Benefits $ 2.0 $ 5.0 $ 3.0
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized 16,000,000    
Percentage Of Fair Market Value Being Expected Purchase Price Of Employee Stock Purchase Plan 95.00%    
Minimum Holding Period for Stock Purchased through Employee Stock Purchase Plan 3 months    
Percentage Of Fair Market Value Being Expected Purchase Price Of Employee Stock Purchase Plan Non Represented 90.00%    
Maximum Percentage Limit Of Base Pay For Employees For Purchasing Shares 10.00%    
Employee Stock Ownership Plan (ESOP), Compensation Expense $ 1.0 $ 1.0  
Shares issued under employee stock purchase plan 373,682 280,077 286,559
Shares issued under employee purchase plan, Average price per share $ 47.26 $ 54.67 $ 47.44
Various [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 13,000,000    
Restricted Stock Units (RSUs) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average grant date fair value of granted shares $ 58.85 $ 56.24 $ 49.34
Unrecognized compensation cost related to stock options expected to be recognized $ 4.0    
Weighted average period for recognizing unrecognized compensation cost 10 months 24 days    
Total intrinsic value of restricted stock units vested $ 11.0 $ 16.0 $ 12.0
Dividend equivalents accrued on stock units 25,920    
Performance Units [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average grant date fair value of granted shares $ 51.79 $ 62.17 $ 54.95
Total intrinsic value of performance units vested $ 19.0 $ 17.0 $ 17.0
Unrecognized compensation cost related to stock options expected to be recognized $ 24.0    
Weighted average period for recognizing unrecognized compensation cost 1 year 8 months 12 days    
Dividend equivalents accrued on stock units 42,925    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 100.00%    
Employee Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 2,200,000    
Minimum | Stock Options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period 1 year    
Minimum | Restricted Stock Units (RSUs) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Options vesting period 3 years    
Minimum | Performance Units [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 0.00%    
Maximum [Member] | Stock Options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Options vesting period 4 years    
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period 10 years    
Maximum [Member] | Performance Units [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Options vesting period 3 years    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 200.00%