(Schedule Of Future Amortization Of Acquisition-Related Intangibles) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Mar. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 16
Finite-Lived Intangible Assets, Amortization Expense, Year Two	11
Finite-Lived Intangible Assets, Amortization Expense, Year Three	11
Finite-Lived Intangible Assets, Amortization Expense, Year Four	11
Finite-Lived Intangible Assets, Amortization Expense, Year Five	8
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	0
Acquisition-related intangibles, net	71	$ 8
Excluding In Process and Research Development [Member]
Finite-Lived Intangible Assets [Line Items]
Acquisition-related intangibles, net	$ 57