Condensed Consolidated Statements Of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net revenue:
Product	$ 481	$ 592	$ 1,183	$ 1,486
Service and other	230	123	483	228
Total net revenue	711	715	1,666	1,714
Cost of revenue:
Product	371	399	503	611
Service and other	74	33	147	61
Total cost of revenue	445	432	650	672
Gross profit	266	283	1,016	1,042
Operating expenses:
Research and development	314	318	604	603
Marketing and sales	212	222	357	362
General and administrative	99	88	185	162
Acquisition-related contingent consideration	0	17	(20)	19
Amortization of intangibles	7	13	14	26
Restructuring and other charges	(2)	(1)	25	17
Total operating expenses	630	657	1,165	1,189
Operating loss	(364)	(374)	(149)	(147)
Interest and other expense, net	(4)	(6)	(9)	(3)
Loss before provision for (benefit from) income taxes	(368)	(380)	(158)	(150)
Provision for (benefit from) income taxes	13	(40)	22	(31)
Net Loss	$ (381)	$ (340)	$ (180)	$ (119)
Net income (loss) per share:
Basic and Diluted	$ (1.21)	$ (1.03)	$ (0.57)	$ (0.36)
Number of shares used in computation:
Basic and Diluted	316	331	317	331