Income Taxes (Balance Sheet Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets
Other noncurrent assets	$ 393	$ 489
Liabilities
Noncurrent deferred tax liabilities	199	833
Net deferred tax assets	$ 194
Net deferred tax liabilities		$ 344

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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