Pension and Other Postretirement Benefits - Schedule of Pension and Postretirement Plans Weighted Average Target and Actual Asset Allocations (Detail)	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	100.00%	100.00%
Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	100.00%	100.00%
Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	20.00%	20.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	65.00%	65.00%
Fixed Income Securities [Member] \| Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	70.00%	57.00%
Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	15.00%	15.00%
Other Investments [Member] \| Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	13.00%	14.00%
Equity Securities [Member] \| Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	17.00%	29.00%

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

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

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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