Other income (expense) (Details) - USD ($) $ in Millions		12 Months Ended
May 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Income and Expenses [Abstract]
Investment and interest income		$ 195	$ 122	$ 74
Foreign exchange gains (losses)		(201)	(213)	(57)
License fee income		125	100	92
Gains (losses) on sale of securities and affiliated companies		4	187	47
Net periodic pension and OPEB income (cost), excluding service cost		(118)	(54)	(664)
Unrealized gain (loss) on investment in equity securities		(33)	0	0
Miscellaneous income (loss)		(39)	11	(10)
Other income (expense)		$ (67)	$ 153	$ (518)
Iron Planet Holdings, Inc. investment
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Realized Gain (Loss) on Disposal	$ 85

This element represents the miscellaneous nonoperating income and loss incurred during the period.

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Amount of expense (reversal of expense) for net periodic pension and postretirement costs excluding the current service cost component. Includes, but is not limited to, interest cost, actual return on plan assets, amortization of loss (gain), amortization of prior service cost (credit), amortization of transition obligation (asset), loss (gain) from a settlement or curtailment, and certain termination benefits.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Amount of income (expense) related to nonoperating activities, classified as other.

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Ancillary revenue earned during the period from the consideration paid to the entity for the use of its rights and property by another party. Examples include licensing the use of copyrighted materials and leasing the extraction of natural resources.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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