Goodwill And Acquisition-Related Intangibles, Net (Schedule Of Amortization Of Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Finite-Lived Intangible Assets Classified by Expense
Amortization of intangibles	$ 4	$ 4	$ 7	$ 8
Cost of service and other
Finite-Lived Intangible Assets Classified by Expense
Amortization of intangibles	9	6	19	12
Cost of product
Finite-Lived Intangible Assets Classified by Expense
Amortization of intangibles	3	8	7	17
Operating expenses
Finite-Lived Intangible Assets Classified by Expense
Amortization of intangibles	4	4	7	8
Total amortization
Finite-Lived Intangible Assets Classified by Expense
Amortization of intangibles	$ 16	$ 18	$ 33	$ 37