Fair Value Measurements and Financial Instruments - Fair Value of Derivative Instruments and Other Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Designated Derivative Instruments [Abstract]
Derivative assets, designated	$ 25	$ 36
Derivative liabilities, designated	73	4
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative assets not designated	0	0
Derivative liabilities not designated	0	0
Total derivative instruments, Assets	25	36
Total derivative instruments, Liabilities	73	4
Financial Instruments, Owned, at Fair Value [Abstract]
Total other financial instruments	14	23
Other current assets
Financial Instruments, Owned, at Fair Value [Abstract]
Marketable securities	14	23
Interest rate swap contracts \| Other current assets
Designated Derivative Instruments [Abstract]
Derivative assets, designated	0	1
Interest rate swap contracts \| Other accruals
Designated Derivative Instruments [Abstract]
Derivative liabilities, designated	0	0
Interest rate swap contracts \| Other assets
Designated Derivative Instruments [Abstract]
Derivative assets, designated	0	1
Interest rate swap contracts \| Other liabilities
Designated Derivative Instruments [Abstract]
Derivative liabilities, designated	7	0
Foreign currency contracts \| Other current assets
Designated Derivative Instruments [Abstract]
Derivative assets, designated	25	29
Foreign currency contracts \| Other accruals
Designated Derivative Instruments [Abstract]
Derivative liabilities, designated	20	4
Foreign currency contracts \| Other assets
Designated Derivative Instruments [Abstract]
Derivative assets, designated	0	5
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative assets not designated	0	0
Foreign currency contracts \| Other liabilities
Designated Derivative Instruments [Abstract]
Derivative liabilities, designated	46	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Derivative liabilities not designated	0	0
Commodity contracts \| Other current assets
Designated Derivative Instruments [Abstract]
Derivative assets, designated	0	0
Commodity contracts \| Other accruals
Designated Derivative Instruments [Abstract]
Derivative liabilities, designated	$ 0	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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