Deferred Revenue (Components Of Deferred Revenue) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Current:
Total current deferred revenue	$ 1,038.6	$ 1,059.5
Long-term:
Total long-term deferred revenue	936.7	934.4
Total deferred revenue	1,975.3	1,993.9
License [Member]
Current:
Total current deferred revenue	319.6	328.0
Long-term:
Total long-term deferred revenue	374.4	362.7
Maintenance [Member]
Current:
Total current deferred revenue	686.5	699.1
Long-term:
Total long-term deferred revenue	560.1	568.1
Professional Services [Member]
Current:
Total current deferred revenue	32.5	32.4
Long-term:
Total long-term deferred revenue	$ 2.2	$ 3.6