Note 5 - Intangible Assets - Expected Future Amortization Expense (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Expected amortization expense, 2020	$ 215
Expected amortization expense, 2021	215
Expected amortization expense, 2022	215
Expected amortization expense, 2023	215
Expected amortization expense, 2024	71
Customer Relationships [Member]
Expected amortization expense, 2020	125
Expected amortization expense, 2021	125
Expected amortization expense, 2022	125
Expected amortization expense, 2023	125
Expected amortization expense, 2024	41
Patents and Trademarks [Member]
Expected amortization expense, 2020	90
Expected amortization expense, 2021	90
Expected amortization expense, 2022	90
Expected amortization expense, 2023	90
Expected amortization expense, 2024	$ 30

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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