Note 8 - Borrowing and Installment Payment Arrangements (Details Textual) € in Thousands, $ in Thousands						1 Months Ended	3 Months Ended	12 Months Ended
		Nov. 20, 2015 USD ($)	Apr. 01, 2015 EUR (€)	Dec. 06, 2013 USD ($)	Jun. 10, 2005 EUR (€)	Apr. 30, 2016 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2016 EUR (€)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Mar. 31, 2016 USD ($)	May. 01, 2015 USD ($)	Apr. 01, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 10, 2005 USD ($)
Bank of West Amended and Restated Credit Agreement December Six Two Thousand and Thirteen [Member]
Line of Credit Facility, Maximum Borrowing Capacity				$ 50,000
Repayments of Lines of Credit									$ 45,000
Line of Credit Facility, Initiation Date				Dec. 06, 2013
Line of Credit Facility, Expiration Date				Nov. 30, 2015
Bank of West Amended and Restated Credit Agreement November 20, 2015 [Member] | Minimum [Member]
Line of Credit Facility Basis Spread on Variable Rate								0.75%				0.75%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage								0.25%	0.25%
Bank of West Amended and Restated Credit Agreement November 20, 2015 [Member] | Maximum [Member]
Line of Credit Facility Basis Spread on Variable Rate								2.50%				2.50%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage								0.625%	0.625%
Bank of West Amended and Restated Credit Agreement November 20, 2015 [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 125,000
Line of Credit Facility, Interest Rate at Period End								2.44%				2.44%
Line of Credit, Leverage Ratio								2	2
Long-term Line of Credit												$ 80,000
Debt Issuance Costs, Net		371										304
Amortization of Debt Issuance Costs									$ 68
Available Credit Line for Letter of Credit		$ 10,000
Line of Credit Facility, Initiation Date		Nov. 20, 2015
Line of Credit Facility, Expiration Date		Nov. 20, 2017
Debt Instrument, Term		2 years
IKB Deutsche Industrial Bank Loan Payable [Member]
Debt Instrument, Face Amount					€ 10,000											$ 12,200
Debt Instrument, Maturity Date					Jun. 30, 2020
Debt Instrument, Issuance Date					Jun. 10, 2005
April 2015 IKB Deutsche Industriebank Loan Payable [Member]
Debt Instrument, Face Amount			€ 6,500											$ 7,200
Debt Instrument, Maturity Date			Mar. 31, 2022
Debt Instrument, Interest Rate, Stated Percentage			1.75%											1.75%
Debt Instrument, Periodic Payment, Principal								€ 232	263
Long-term Debt, Gross								€ 5,600				6,300
Notes Payable, Other Payables [Member] | RadioPulse [Member] | Subsequent Event [Member]
Repayments of Debt						$ 684
Notes Payable, Other Payables [Member] | RadioPulse [Member]
Long-term Debt, Gross												684
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt													$ 2,400
Debt Instrument, Interest Rate, Effective Percentage													4.90%
Notes Payable, Other Payables [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt															$ 723
Repayments of Debt							$ 99
Debt Issuance Costs, Net												304
Long-term Debt, Gross	[1]											$ 85,557
Repayments of Debt									$ 47,606	$ 1,144	$ 1,000

[1] Includes approximately $304,000 of unamortized debt issuance cost.