Segment Information - Schedule of Segment Reporting Information to Consolidated Assets (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total segment assets	$ 18,219	$ 18,718
Cash and cash equivalents	1,455	2,150
Corporate fixed assets, net	5,582	5,594
Operating Segments
Segment Reporting Information [Line Items]
Total segment assets	15,687	15,321
Segment Reconciling Items
Segment Reporting Information [Line Items]
Cash and cash equivalents	1,455	2,150
Deferred income taxes	626	743
Corporate fixed assets, net	304	310
Fair value of derivative contracts	57	91
Other	$ 90	$ 103

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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