Deferred Revenue (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Current:
Total deferred revenue (billed or collected) - current	$ 2,038	$ 2,482
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	856	975
Total deferred revenue (billed or collected)	2,894	3,457
Subscription and Maintenance [Member]
Current:
Total deferred revenue (billed or collected) - current	1,882	2,307
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	824	940
Professional Services [Member]
Current:
Total deferred revenue (billed or collected) - current	136	154
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	30	33
Software Fees and Other [Member]
Current:
Total deferred revenue (billed or collected) - current	20	21
Noncurrent:
Total deferred revenue (billed or collected) - noncurrent	$ 2	$ 2