Other Expense (Income), Net - Schedule (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Income and Expenses [Abstract]
Non-service related net periodic benefit cost	$ 28	$ 39	$ 56	$ 77
Interest income	(4)	(4)	(10)	(8)
Foreign currency gains (losses), net	17	2	14	(3)
Net loss (gain) from asset sales	2	(166)	5	(515)
Other, net	(2)	(3)	(4)	1
Total	$ 41	$ (132)	$ 61	$ (448)

Net Periodic Benefit Cost, Non-service

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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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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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- Definition

The net amount of nonoperating interest income (expense).

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No definition available.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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

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