Employee Benefits - Weighted Average Assumptions Used In Determining Net Periodic Cost (Detail)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension
Defined Benefit Plan Disclosure [Line Items]
Discount rate in effect for determining service cost	5.40%	5.30%	3.80%
Discount rate in effect for determining interest cost	5.20%	5.10%	3.20%
Expected return on plan assets	7.90%	7.70%	6.70%
Rate of compensation increases	3.00%	3.00%	3.00%
Health Care and Life
Defined Benefit Plan Disclosure [Line Items]
Discount rate in effect for determining service cost	5.10%	5.30%	3.20%
Discount rate in effect for determining interest cost	4.90%	5.10%	2.30%
Expected return on plan assets	6.30%	7.30%	4.90%