Pensions and Other Benefit Plans - Projected Future Minimum Contributions to the Company's U.S. and International Unfunded Retirement Plans (Details) $ in Millions	Dec. 31, 2017 USD ($)
Retirement Benefits [Abstract]
2018	$ 88
2019	89
2020	94
2021	100
2022	108
2023-2027	$ 651

Defined benefit plan expected future benefit contribution in five fiscal years thereafter.

No definition available.

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Defined benefit plan expected future benefit contribution in year five.

No definition available.

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Defined benefit plan expected future benefit contribution in year four.

No definition available.

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Defined benefit plan expected future benefit contribution in year one.

No definition available.

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Defined benefit plan expected future benefit contribution in year three.

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Defined benefit plan expected future benefit contribution in year two.

No definition available.

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No definition available.

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