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Retirement Plans - Schedule of Weighted-Average Assumptions Used to Determine Benefit Obligation (Detail) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Net Periodic Benefit Cost Assumptions [Line Items] |  |  |
Discount Rate | 4.90% | 5.31% | 2.38%
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

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- Definition Defined Benefit Plan Initial Health Care Cost Trend Rate + References No definition available. + Details
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- Definition Net Periodic Benefit Cost Assumptions [Line Items] + References No definition available. + Details
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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 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + 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 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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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 + Details
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