(Schedule Of Royalty-Related Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Mar. 31, 2016
Royalties And Licenses [Line Items]
Royalty-related assets	$ 118	$ 117
Other Current Assets [Member]
Royalties And Licenses [Line Items]
Royalty-related assets	79	54
Other Assets [Member]
Royalties And Licenses [Line Items]
Royalty-related assets	$ 39	$ 63