Acquisitions - Additional Information (Detail) (USD $)	6 Months Ended			6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011 Y	Mar. 31, 2012	Sep. 30, 2012 Accanto Systems Srl	Jul. 20, 2012 Accanto Systems Srl	Sep. 30, 2012 Simena	Nov. 18, 2011 Simena	Oct. 03, 2011 Replay	Apr. 01, 2011 Psytechnics
Business Acquisition [Line Items]
Preliminary purchase price allocation period, years		1
Total purchase price					$ 15,000,000		$ 10,100,000	$ 20,200,000	$ 17,000,000
Acquired software intangible, tax deductible amount	2,100,000
Weighted average useful life of identifiable intangible assets acquired	10 years 6 months			7 years 3 months 18 days
Acquisition-related costs				586,000
Additional purchase price consideration						10,800,000
Fair value of contingent liability	6,488,000		8,213,000			8,000,000
Business acquisition, revenue recorded	$ 8,400,000