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Employee Benefit Plans (Performance Shares and Compensation Expense) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Performance Share Units (PSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded (in shares) 313,100 247,000.0 356,100
Percentage of award paid in stock 50.00%    
Percentage of award paid in cash 50.00%    
Performance period 3 years    
Compensation expense $ 47.1 $ 17.2 $ 22.5
Total unrecognized compensation expense related to outstanding restricted stock units and restricted shares $ 22.5    
Weighted average period for compensation expense recognition 1 year    
Performance Share Units (PSUs) | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded after performance period, as a percentage of targeted amount 0.00%    
Performance Share Units (PSUs) | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded after performance period, as a percentage of targeted amount 150.00%    
Performance Shares Earned as Dividend Equivalents      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded (in shares) 13,586 16,760 17,612
Executive Officer | Performance Share Units (PSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded (in shares) 181,322 127,278 166,179
Employees Other Than Named Executive Officers | Performance Share Units (PSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares awarded (in shares) 118,168 102,994 172,341
Percentage of award paid in stock 100.00%    
Chief Executive Officer | Performance Share Units (PSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense $ 16.0