Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accrued Liabilities [Abstract]
Advances on sales contracts and service billings	$ 0	$ 4,547
Accrued salaries, wages and employee benefits	2,074	1,741
Service and warranty accruals	754	629
Interest payable	637	439
Litigation and contract matters	461	435
Income taxes payable	460	285
Accrued property, sales and use taxes	277	258
Canadian government settlement - current portion	34	217
Accrued restructuring costs	249	212
Accrued workers compensation	142	204
Liabilities held for sale	40	0
Other	5,095	3,349
Accrued liabilities	$ 10,223	$ 12,316

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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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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The current portion of prepayments received from customers for goods or services to be provided in the future.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. 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 [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 incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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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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Carrying value as of the balance sheet date of obligations, incurred through that date and payable for property, sales and use taxes.

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Canadian government settlement - current portion

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Liabilities held for sale

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Carrying value as of the balance sheet date of accrued litigation and contract matters. 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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