Retirement and Other Benefit Plans - Schedule of Target Assets Allocation (Detail)	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	100.00%
Total	100.00%	100.00%
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	56.00%
Total	58.00%	53.00%
Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	28.00%
Total	22.00%	27.00%
Real Estate
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	10.00%
Total	10.00%	12.00%
Private infrastructure
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	6.00%
Total	8.00%	8.00%
Cash
Defined Benefit Plan Disclosure [Line Items]
Other securities, Target Allocation	0.00%
Total	2.00%	0.00%

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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