Income Taxes (Schedule Of Differences Between Statutory Tax Rate And Effective Tax Rate) (Details)
12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Income Tax Expense Reconciliation [Line Items]      
Statutory federal tax expense (benefit) rate 35.00% 35.00% 35.00%
State taxes, net of federal benefit 0.10% (242.90%) (5.00%)
Differences between statutory rate and foreign effective tax rate (22.30%) (142.90%) (15.20%)
Valuation allowance (9.20%) 936.50% 35.00%
Research and development credits (1.10%) (128.60%) (8.60%)
Differences between book and tax loss on strategic investments 0.00% 0.00% (15.20%)
Effective Income Tax Rate Reconciliation, Tax Settlement, Percent (0.50%) (657.10%) 0.00%
Non-deductible stock-based compensation 3.50% 385.70% 21.50%
Acquisition-related contingent consideration (0.20%) (185.70%) (16.50%)
Other 0.10% (14.30%) (1.50%)
Effective tax expense (benefit) rate 5.40% (14.30%) 29.50%