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Retirement Plans, Postretirement and Postemployment Benefits - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]      
Accumulated benefit obligation for defined benefit pension plans $ 789.6 $ 1,000.0  
Combined pension plan and SERP contributions 90.2 82.8  
Estimated contribution of pension plans 36.5    
Corporation's matching obligations $ 23.1 $ 20.5 $ 17.9
Defined contribution plan name 401(a)    
Defined benefit plans remeasurement increased $ 47.6    
Postretirement Health Care Plans [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Estimated contribution of pension plans $ 1.0