Goodwill And Acquisition-Related Intangibles, Net (Schedule Of Amortization Of Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 1	$ 2
Cost of service and other
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	0	8
Cost of product
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	0	5
Operating expenses
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	1	2
Total amortization
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 1	$ 15