Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Details)

v2.4.1.9
Stockholders' Equity (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Stock-Based Compensation      
Stock-based compensation expense $ 2,236us-gaap_AllocatedShareBasedCompensationExpense $ 2,147us-gaap_AllocatedShareBasedCompensationExpense $ 1,601us-gaap_AllocatedShareBasedCompensationExpense
Cost of goods sold      
Stock-Based Compensation      
Stock-based compensation expense 113us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_CostOfSalesMember 		43us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_CostOfSalesMember 		92us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_CostOfSalesMember
Research and development      
Stock-Based Compensation      
Stock-based compensation expense 328us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_ResearchAndDevelopmentExpenseMember 		562us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_ResearchAndDevelopmentExpenseMember 		319us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_ResearchAndDevelopmentExpenseMember
Selling, general and administrative      
Stock-Based Compensation      
Stock-based compensation expense $ 1,795us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember 		$ 1,542us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember 		$ 1,190us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember