Intangible Assets (Schedule Of Intangible Assets) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Finite And Indefinite Lived Intangible Assets [Line Items]
Document Fiscal Year Focus	2017
Document Period End Date	Mar. 31, 2017
Amortized Intangible Assets, Gross Carrying Amount	$ 531	$ 531
Amortized Intangible Assets, Accumulated Amortization	223	211
Amortized Intangible Assets, Net Carrying Amount	308	320
Unamortized Intangible Assets, Goodwill, Gross Carrying Amount	1,013	1,007
License agreements
Finite And Indefinite Lived Intangible Assets [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	260	261
Amortized Intangible Assets, Accumulated Amortization	115	109
Amortized Intangible Assets, Net Carrying Amount	145	152
Customer relationships
Finite And Indefinite Lived Intangible Assets [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	226	224
Amortized Intangible Assets, Accumulated Amortization	96	90
Amortized Intangible Assets, Net Carrying Amount	130	134
Other
Finite And Indefinite Lived Intangible Assets [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	45	46
Amortized Intangible Assets, Accumulated Amortization	12	12
Amortized Intangible Assets, Net Carrying Amount	33	34
Goodwill
Finite And Indefinite Lived Intangible Assets [Line Items]
Unamortized Intangible Assets, Goodwill, Gross Carrying Amount	1,013	1,007
Trademarks
Finite And Indefinite Lived Intangible Assets [Line Items]
Unamortized Intangible Assets, Trademarks, Gross Carrying Amount	$ 551	$ 550