Supplemental Financial Information - Accrued Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Accrued Liabilities, Current [Abstract]
Extended Emergency Time Off	$ 17	$ 393
Voluntary Separation Program	98	143
Profitsharing and savings plans	210	25
Vendor prepayment	0	600
Vacation pay	450	436
Health	137	111
Workers compensation	141	161
Property and income taxes	78	84
Interest	110	49
Deferred supplier payments	142	0
Other	304	257
Accrued liabilities	$ 1,687	$ 2,259

Accrual for Property and Income Taxes

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- Definition

Deferred Supplier Payments, Current

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- Definition

Proceeds from Payroll Support Program Grant Remaining to be Allocated to Payroll Support, Voluntary Separation, net

+ References

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- Definition

Vendor Prepayment

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- Definition

Voluntary Separation Program 2020 Accrued Liability

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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).

+ References

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-Name Accounting Standards Codification
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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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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).

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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.

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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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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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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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