Deferred Revenue (Details) (USD $) In Millions	Sep. 30, 2011	Mar. 31, 2011
Current:
Total deferred revenue (billed or collected) - current	$ 2,175	$ 2,600
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	863	969
Total deferred revenue (billed or collected)	3,038	3,569
Subscription and maintenance [Member]
Current:
Total deferred revenue (billed or collected) - current	2,020	2,444
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	831	940
Professional services [Member]
Current:
Total deferred revenue (billed or collected) - current	142	145
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	30	27
Financing obligations and other [Member]
Current:
Total deferred revenue (billed or collected) - current	13	11
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	$ 2	$ 2