Note 11 - Derivative Financial Instruments - Fair Value of Swaps Recognized in Accrued Liabilities and in Other Comprehensive Income (Details) - USD ($) $ in Thousands	9 Months Ended
Mar. 31, 2020	Jun. 30, 2019
Fair Value, Liability	$ (5,512)	$ (1,380)
Interest Rate Swap Effective December 19, 2015 [Member]
Notional Amount	$ 10,000
Fixed Rate	2.01%
Maturity	Dec. 19, 2019
Fair Value, Asset	$ 0	(3)
Fair Value, Asset	(0)	3
Interest Rate Swap Effective May 24, 2017 Number One [Member]
Notional Amount	$ 25,000
Fixed Rate	1.88%
Maturity	Apr. 24, 2022
Fair Value, Liability	$ (848)	(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)
Fair Value, Asset		49
Fair Value, Liability	$ (35)
Interest Rate Swap Effective August 6, 2018 [Member]
Notional Amount	$ 25,000
Fixed Rate	2.83%
Maturity	Aug. 06, 2023
Fair Value, Liability	$ (2,169)	(1,242)
Interest Rate Swap Effective March 23, 2020 [Member]
Notional Amount	$ 100,000
Fixed Rate	0.91%
Maturity	Mar. 23, 2025
Fair Value, Liability	$ (1,673)	0
Interest Rate Swap Effective April 24, 2020 [Member]
Notional Amount	$ 25,000
Fixed Rate	0.88%
Maturity	Apr. 24, 2025
Fair Value, Liability	$ (377)	0
Interest Rate Swap Effective May 24, 2020 [Member]
Notional Amount	$ 25,000
Fixed Rate	0.91%
Maturity	Mar. 24, 2025
Fair Value, Liability	$ (410)	$ 0

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.

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=121590274&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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Balance Type:	credit
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Fair value of asset associated with financial liability or 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 210
-SubTopic 20
-Section 50
-Paragraph 3
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-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=121590274&loc=SL5624163-113959

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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