Note 1 - Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Jun. 30, 2017 USD ($) shares	Jun. 30, 2016 USD ($) shares	Jun. 30, 2015 USD ($) shares
Number of Revenue Sources	5
Cash, FDIC Insured Amount	$ 250,000
Cash, Uninsured Amount	4,488,000	$ 37,883,000
Depreciation	7,005,000	6,171,000	$ 5,804,000
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	0
Defined Contribution Plan, Cost	2,373,000	2,327,000	1,880,000
Research and Development Expense	$ 5,700,000	$ 5,549,000	$ 5,598,000
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares | shares	844,000	872,000	451,000
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	$ 0
Minimum [Member]
Media Content Service Period	30 days
Finite-Lived Intangible Asset, Useful Life	7 years
Standard Warranty Term	1 year
Maximum [Member]
Media Content Service Period	1 year
Finite-Lived Intangible Asset, Useful Life	20 years
Standard Warranty Term	5 years
Maximum [Member] | Product Warranty Exceptions [Member]
Standard Warranty Term	10 years
Maximum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life	15 years