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Employee Benefits - Weighted Average Assumptions Used to Determine Postretirement Benefit Expense and Obligation (Detail) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Liability |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 5.10% | 5.40%
Current medical cost trend rate | 7.25% | 6.50%
Ultimate medical cost trend rate | 4.75% | 4.75%
Expense |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 5.40% | 2.90%
Current medical cost trend rate | 6.50% | 6.75%
Ultimate medical cost trend rate | 4.75% | 4.75%

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- Definition The current medical cost trend rate utilized to determine postretirement benefit expense. + 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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