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Employee Benefits - Asset Target Allocations Prescribed by Trusts' Investment Policies (Details)	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Target allocation	100.00%
U.S. equity securities | Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Target allocation	64.00%
International equity securities | Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Target allocation	16.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Target allocation	84.00%
Fixed income securities | Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Target allocation	20.00%

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+ References

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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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