Stock-Based Compensation And Employee Benefit Plans (Schedule Of Stock-Based Compensation Expense By Statement Of Operations Line Item) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Mar. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 164		$ 170		$ 176
Cost of revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	2		2		2
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	94	[1]	103	[1]	107	[1]
Marketing and sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	30	[1]	27	[1]	23	[1]
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	38	[1]	38	[1]	42	[1]
Restructuring and other charges [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 0		$ 0		$ 2

[1] During the fourth quarter of fiscal year 2013, we reviewed our operating expenses and reclassified certain amounts, primarily headcount and facilities costs, to align with our current operating structure. As a result, we also reclassified the related prior year stock-based compensation expense amounts within our Consolidated Statements of Operations for comparability purposes. These reclassifications did not affect the Company's total stock-based compensation expense.