Note 2 - Summary of Significant Accounting Policies - Warranty Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2017
Balance at beginning of the period	$ 7,560	$ 5,069	$ 5,069
Additions charged to expense	3,813	3,841	4,956
Addition from acquired company		907	907
Deductions for repairs and replacements	(4,652)	(2,283)	(3,372)
Balance at end of the period	$ 6,721	$ 7,534	$ 7,560

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Amount of increase in the standard product warranty accrual from a business acquisition. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(2))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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