Note 17 - Employee Benefit Plans (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	$ 17,300
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	17,100
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	17,500
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	87,800
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	1,400
Defined Benefit Plan, Accumulated Benefit Obligation	301,600	$ 310,400
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year	(5,500)
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year	(100)
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	17,400
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	$ 17,200
Retirement Savings Plans [Member]
Defined Contribution Plans Number of Plans	2
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 4,000	4,000	$ 3,800
Retirement Savings Plans [Member] \| Salaried Employees [Member]
Defined Contribution Plans Number of Plans	1
Defined Contribution Plan Company Stock Held in Plan	72,000
Defined Contribution Plan Company Stock, Percentage of Plan Assets	6.00%
Retirement Savings Plans [Member] \| Hourly Employees [Member]
Defined Contribution Plans Number of Plans	1
Postretirement Health Coverage [Member] \| Maximum [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 100	100
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	100	100	100
Defined Benefit Plan, Accumulated Benefit Obligation	200	200
UNITED STATES
Defined Benefit Plan, Plan Assets, Contributions by Employer	284	206
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ 1,453	$ 1,688	$ 976
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	7.10%

The amount of outstanding options held by the defined contribution plan.

No definition available.

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- Definition

The percentage of the monetary value of outstanding stock options against the value of outstanding plan assets.

+ References

No definition available.

+ Details

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- Definition

The number of defined contribution plans.

+ References

No definition available.

+ Details

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

+ Details

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

+ References

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- Definition

Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

+ References

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- Definition

Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

+ References

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

+ Details

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

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