Employee Benefit Plans (The Weighted-Average Discount Rate Assumptions Used to Determine Net Periodic Benefit Costs) (Detail) - Unfunded Supplemental Benefit Plans	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Discount rates:
Projected benefit obligation	5.21%	5.56%	2.89%
Service cost	5.40%	5.75%	3.29%
Interest cost	5.15%	5.45%	2.37%

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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