Retirement Plans - Schedule of Weighted-Average Assumptions Used to Determine Benefit Obligation (Detail)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Net Periodic Benefit Cost Assumptions [Line Items]
Discount Rate	4.81%	5.33%	4.90%
Health care cost trend: Ultimate	4.75%	4.75%	4.75%
Year ultimate reached	2034	2033	2029
Net Periodic Cost [Member]
Net Periodic Benefit Cost Assumptions [Line Items]
Defined Benefit Plan, Assumed Health Care Cost Trend Rate, Description	8.70	7.45	6.95
Year ultimate reached	2033	2029	2028

Net Periodic Benefit Cost Assumptions [Line Items]

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: 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

+ Details

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- Definition

Description of direction and pattern of change in assumed health care cost trend rate used to measure expected cost of benefits for defined benefit postretirement plan.

+ References

No definition available.

+ Details

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (k)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

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

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

+ References

+ Details

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