Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Other Asset Impairment Charges		$ 5
Impairment of Intangible Assets (Excluding Goodwill)	$ 4
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	136	131
Property, Plant and Equipment, Gross	270
Depreciation	15	16	$ 17
Goodwill	7	7
Values Of Business Acquired Distribution Agreements And Customer Relationships	12	19
Accumulated Amortization Of Values Of Business Acquired Distribution Agreements And Customer Relationships	109	102
Amortization Of Values Of Business Acquired Distribution Agreements And Customer Relationships	6	7	8
Finite-Lived Intangible Assets, Amortization Expense, Year Two	6
Finite-Lived Intangible Assets, Amortization Expense, Year Three	6
Capitalized Computer Software, Net	138	145
Capitalized Computer Software, Amortization	$ 24	27	$ 32
Value of Customer Relationships Acquired [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Value of Distribution Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization Of Values Of Business Acquired Distribution Agreements And Customer Relationships	$ 20	$ 17
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	3
Finite-Lived Intangible Assets, Amortization Expense, Year Two	3
Finite-Lived Intangible Assets, Amortization Expense, Year Three	3
Finite-Lived Intangible Assets, Amortization Expense, Year Four	$ 3