Income Taxes (Classification of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Non-current assets	$ 256	$ 226
Non-current liabilities	(242)	(310)
Deferred Tax Assets, Net	$ 14
Total net deferred tax liabilities		$ 84

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31931-109318

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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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