Annual report pursuant to Section 13 and 15(d)

Organization and Significant Accounting Policies (Details 4)

v2.4.0.6
Organization and Significant Accounting Policies (Details 4) (USD $)
12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Mar. 31, 2011
Fair Value Measurement      
Money markets $ 30,000,000 $ 26,200,000  
Revenue Recognition      
Percentage of relevant inventory evaluated for SFSD reserve 86.00%    
Percentage of total inventory purchased in previous quarter that can be returned by the distributors, maximum 6.00%    
Period of product warranty 1 year    
Warranty costs as a percentage of net sales, maximum 1.00% 1.00% 1.00%
Shipping and Handling Costs      
Shipping and Handling Costs 21,100,000 22,800,000 24,800,000
Carrying Value
     
Fair Value Measurement      
Money markets 29,984,000 26,215,000  
Long-term debt 383,500,000 347,331,000  
Recurring | Fair Value
     
Fair Value Measurement      
Money markets 29,984,000 26,215,000  
Long-term debt 393,928,000 362,086,000  
Recurring | Level 1 | Fair Value
     
Fair Value Measurement      
Money markets 29,984,000 26,215,000  
Long-term debt 369,200,000 358,700,000  
Recurring | Level 2 | Fair Value
     
Fair Value Measurement      
Long-term debt $ 24,728,000 $ 3,386,000