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Stock-Based Compensation - Schedule of Restricted Stock Activity (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock compensation expense $ 4.7 $ 9.6 $ 8.9  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]        
Ending Balance $ 3,227.5 $ 3,073.8 1,986.6 $ 1,959.8
Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 683,574     (86,802)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]        
Restricted stock, beginning of year, number of shares 741,098      
Granted, number of shares 683,574      
Vested, number of shares (180,587)      
Forfeited, number of shares (127,779)      
Restricted stock, end of year, number of shares 1,116,306 741,098    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]        
Restricted stock, beginning of year, weighted-average measurement date fair value (in dollars per share) $ 38.94      
Granted, weighted average grant date fair value (in dollars per share) 19.84      
Vested, weighted average grant date fair value (in dollars per share) 36.73      
Forfeited, weighted average grant date fair value (in dollars per share) 29.75      
Restricted stock, end of year, weighted-average measurement date fair value (in dollars per share) $ 27.74 $ 38.94    
Tax benefits from stock-based compensation $ (0.4) $ (0.3) (0.3)  
Unrecognized compensation cost related to nonvested restricted stock awards $ 22.2      
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition 1 year 4 months 6 days      
Common Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock compensation expense $ 4.7 9.6 8.9  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]        
Ending Balance $ 2,448.9 $ 2,478.2 $ 945.0 $ 941.1
Upon Achievement of Defined Total Return to Shareholder Goals | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 181,720      
Upon One-Third Annual Anniversary | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 254,857      
Upon Achievement of Performance Goals | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 363,440      
Upon Achievement of Defined Return on Equity Performance Goals | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 181,720      
One Year from Grant Date | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 54,414      
Time-restricted shares | Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock issued during period, shares, restricted stock award 406,936