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Business, Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)	Aug. 04, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of segments \| Segment	3
Parent shareholders' percentage [Member] \| Spinoff [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Common Stock Distribution by Parent			80.80%
Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 15
Retained Earnings (Deficit) \| Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 38
Distribution Rights [Member] \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Distribution Rights [Member] \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Finite-Lived Intangible Asset, Useful Life	40 years
Deferred Income Tax [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 22
Other Liabilities [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	46
Retained Earnings (Deficit)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	40
Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 64