Foreign Currency Transactions and Derivatives (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Mar. 31, 2011
Foreign Currency Transactions and Derivatives [Abstract]
Foreign currency net gain (loss) resulting from anticipated transactions and inter-company balances	$ 138,000	$ (464,000)	$ 707,000	$ (1,100,000)
Hedging transaction net gain (loss) from foreign exchange derivative contracts	98,000	2,500	(490,000)	21,500
Derivative contract maturing through Jan 2012	3,400,000		3,400,000		3,300,000
Amount of derivative contracts to purchase	$ 8,900,000		$ 8,900,000		$ 5,700,000