Commitments And Contingencies (Narrative) (Details) (USD $)	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Commitments And Contingencies [Line Items]
Fair value of contingent liability	$ 8,213,000	$ 0	$ 0
Contractual non-compliance liabilities incurred by Simena	700,000
Total rent expense under non-cancelable operating leases	5,600,000	5,600,000	6,500,000
Simena, LLC [Member]
Commitments And Contingencies [Line Items]
Fair value of contingent liability	8,000,000
Contractual non-compliance liabilities incurred by Simena	1,600,000
Present Value Of Future Consideration [Member] | Simena, LLC [Member]
Commitments And Contingencies [Line Items]
Fair value of contingent liability	8,200,000
Contractual non-compliance liabilities incurred by Simena	$ 700,000