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Retirement Plans - Schedule of Weighted-Average Assumptions Used to Determine Net Periodic Cost (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Periodic Benefit Cost Assumptions [Line Items]
Discount rate	5.31%	2.38%	1.83%
Health care cost trend: Initial	6.95%	6.50%	5.90%
Health care cost trend: Ultimate	4.75%	4.75%	4.75%
Year ultimate reached	2029	2028	2027
Corridor	10.00%	10.00%	10.00%
Recognition period for gains and losses	9 years 3 months 18 days	9 years 10 months 24 days	10 years 4 months 24 days
Net Periodic Cost [Member]
Net Periodic Benefit Cost Assumptions [Line Items]
Health care cost trend: Initial	6.50%	5.90%	5.95%
Year ultimate reached	2028	2027	2026

X

- Definition

Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Recognized Period

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- Definition

Defined Benefit Plan Corridor Rate

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- Definition

Defined Benefit Plan Initial Health Care Cost Trend Rate

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- Definition

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 net periodic benefit cost 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 1
-Subparagraph (k)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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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 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

Reference 1: 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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