(Schedule Of Amortization Of Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 22	$ 23	$ 9
Cost of revenue [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	12	4	2
Operating expenses
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	22	23	9
Total amortization
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 34	$ 27	$ 11