Goodwill And Acquisition-Related Intangibles, Net (Narrative) (Details)	6 Months Ended	12 Months Ended
	Sep. 30, 2012	Mar. 31, 2012
Minimum
Finite-Lived Intangible Assets
Finite-Lived Intangible Asset, Useful Life	2 years
Maximum
Finite-Lived Intangible Assets
Finite-Lived Intangible Asset, Useful Life	14 years
Weighted Average
Finite-Lived Intangible Assets
Finite-Lived Intangible Asset, Useful Life	5 years 4 months	5 years 8 months 12 days