Note 11 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent										21.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability										$ 6,300
Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings, Income Tax Credit									$ (1,800)
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment									$ 0
Additional Tax Rate On Foreign Income									10.50%
Effective Income Tax Rate Reconciliation, Percent, Total									36.70%	174.70%	35.60%
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	$ 2,632	$ 3,045	$ 2,991	$ 942	$ 791	$ 2,337	$ 1,097	$ 640	$ 9,610	$ 4,865	$ 1,538
Effective Income Tax Rate Reconciliation, Before Tax Cuts and Jobs Act, Percent										44.70%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount									(129)	$ 6,324	315
Proceeds from Equity Method Investment, Distribution											2,000
Deferred Tax Assets, Gross, Total	18,600								18,600
Deferred Tax Assets, Net of Valuation Allowance, Total	22,400								22,400
Deferred Tax Assets, Valuation Allowance, Total	6,743				4,999				6,743	4,999
Unrecognized Tax Benefits, Ending Balance	10,939				10,882				10,939	10,882	11,588	$ 10,820
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	5,600				5,400				5,600	5,400	7,300
Income Taxes Receivable, Noncurrent	1,666				$ 1,820				1,666	1,820
Undistributed Earnings of Foreign Subsidiaries	67,900								67,900
Foreign Earnings Repatriated											$ 2,000
Research Tax Credit Carryforward [Member]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	800								800
Foreign Tax Authority [Member]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount									1,700	$ 2,100
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	300								300
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	7,300								7,300
Domestic Tax Authority [Member]
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	300								300
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	1,200								1,200
State and Local Jurisdiction [Member]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	$ 400								$ 400
Her Majesty's Revenue and Customs (HMRC) [Member]
Effective Income Tax Rate Reconciliation, Percent, Total											17.00%	20.00%