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Employee Benefits - Weighted Average Assumptions Used to Determine Postretirement Benefit Expense and Obligation (Detail)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Liability
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.70%	5.10%
Current medical cost trend rate	7.00%	7.25%
Ultimate medical cost trend rate	4.75%	4.75%
Expense
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%

X

- Definition

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

+ References

No definition available.

+ Details

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X

- 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

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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X

- 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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