Supplemental Financial Information - Accrued Liabilities (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Voluntary Separation Program	$ 64	$ 65
Profitsharing and savings plans	63	141
Vacation pay	578	516
Health	183	163
Workers compensation	141	133
Property and income taxes	70	63
Interest	34	34
Bonus and incentive pay	186	2,022
Reinsurance payable	282	190
Other	269	279
Accrued liabilities	1,870	$ 3,606
Payment of bonus and incentive pay as a ratification of the labor contract agreement	$ 1,900

Accrual for Property And Income Taxes

No definition available.

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- Definition

Reinsurance Payable, Current

+ References

No definition available.

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- Definition

Voluntary Separation Program 2020 Accrued Liability

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for unused vacation time owed to employees based on the entity's vacation benefit given to its employees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 25
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483070/710-10-25-3

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable within one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483043/710-10-30-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 25
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483070/710-10-25-15

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

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- Definition

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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- Definition

Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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