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Employee Benefit Plans - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]        
Defined contribution plan, expense recognized   $ 11.1 $ 9.8 $ 8.4
Inactive participants In defined benefit plan   99.00%    
Benefit obligation, discount rate   25.00%    
Decrease in expense for all pension plans   $ (0.3)    
Hedge Funds [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Quarterly redemption restriction notice period   65 days    
Defined Benefit Pension Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Contribution to defined benefit plan assets   $ 106.9 $ 19.8  
Benefit obligation, discount rate   1.87% 2.81% 3.92%
Reduction in projected benefit obligation, mortality assumptions   $ (6.0) $ (8.5)  
Fair value of plan assets exceeded projected benefit obligation of defined benefit plans   3.5    
Projected benefit obligation of defined benefit plans exceeded the fair value of plan assets     121.6  
Accumulated benefit obligation of defined benefit plans   $ 555.2 547.2  
Defined Benefit Pension Plan [Member] | Long Term Investments [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan assets percentage of asset categories   15.00%    
Defined Benefit Pension Plan [Member] | Liability Hedging [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan assets percentage of asset categories   83.00%    
Defined Benefit Pension Plan [Member] | Short-term Investments [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan assets percentage of asset categories   2.00%    
Defined Benefit Pension Plan [Member] | Fixed Income [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan percentage of target allocation   25.00%    
Defined Benefit Pension Plan [Member] | Public Equity [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan percentage of target allocation   62.00%    
Defined Benefit Pension Plan [Member] | Alternate Investments [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Defined benefit plan percentage of target allocation   13.00%    
Defined Benefit Pension Plan [Member] | United States [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Pension plan contributed amount   $ 105.0    
Pension plan minimum contributions   17.0    
Pension plan, voluntary contributions   88.0    
Nonqualified Defined Benefit Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Contribution to defined benefit plan assets   1.9    
Nonqualified Defined Benefit Plan [Member] | Scenario, Forecast [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Contribution to defined benefit plan assets $ 1.6      
Other Postretirement Benefits Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Contribution to defined benefit plan assets   $ 1.6 $ 1.2  
Benefit obligation, discount rate   1.42% 2.52% 3.70%
The year the health care cost reaches ultimate trend rate of 4.5%   2028    
Assumed health care cost trend rate used in measuring the benefit obligation   The assumed health care cost trend rate represents the rate at which health care costs are assumed to increase. The assumed health care cost trend rate used in measuring the benefit obligation in 2020 is 6.4% for pre-age 65 retirees and 7.1% for post-age 65 retirees. These rates are assumed to decrease gradually to the ultimate health care cost trend rate of 4.5% in 2028 for both groups.    
Other Postretirement Benefits Plan [Member] | Pre Age 65 [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Assumed health care cost trend rate   6.40%    
Other Postretirement Benefits Plan [Member] | Post Age 65 [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Assumed health care cost trend rate   7.10%