Income Taxes (Net Deferred Tax Asset (Liability)) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
Deferred tax liability	$ (461)	$ (588)
Net deferred tax liability	(424)	(555)
Other Noncurrent Assets
Income Tax Contingency [Line Items]
Deferred tax asset	37	33
Other Noncurrent Liabilities
Income Tax Contingency [Line Items]
Deferred tax liability	$ (461)	$ (588)

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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