Note 10 - Derivative Financial Instruments - Fair Value of Swaps Recognized in Accrued Liabilities and in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Fair Value, Asset		$ 1,325
Fair Value, Liability	$ (1,380)
Interest Rate Swap Effective December 18, 2015 [Member]
Notional Amount	$ 15,000
Fixed Rate	1.46%
Maturity	Dec. 19, 2018
Fair Value, Asset		55
Interest Rate Swap Effective December 19, 2015 [Member]
Notional Amount	$ 10,000
Fixed Rate	2.01%
Maturity	Dec. 19, 2019
Fair Value, Asset	$ 3	74
Interest Rate Swap Effective May 24, 2017 Number One [Member]
Notional Amount	$ 25,000
Fixed Rate	1.88%
Maturity	Apr. 24, 2022
Fair Value, Asset		764
Fair Value, Liability	$ (190)
Interest Rate Swap Effective May 24, 2017 Number Two [Member]
Notional Amount	$ 25,000
Fixed Rate	1.67%
Maturity	May 24, 2020
Fair Value, Asset	$ 49	$ 432
Interest Rate Swap Effective August 6, 2018 [Member]
Notional Amount	$ 25,000
Fixed Rate	2.83%
Maturity	Aug. 06, 2023
Fair Value, Liability	$ (1,242)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

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