Note 16 - Employee Benefit Plans - Asset Allocation (Details)	Jun. 30, 2020	Jun. 30, 2019
UNITED STATES
Asset allocations	100.00%	100.00%
Foreign Plan [Member]
Asset allocations	100.00%	100.00%
Equity Securities [Member] | UNITED STATES
Asset allocations	41.00%	31.00%
Equity Securities [Member] | Foreign Plan [Member]
Asset allocations	5.00%	20.00%
Debt Securities [Member] | UNITED STATES
Asset allocations	38.00%	35.00%
Debt Securities [Member] | Foreign Plan [Member]
Asset allocations	64.00%	41.00%
Hedge Funds, Global Opportunity [Member] | UNITED STATES
Asset allocations	11.00%	24.00%
Hedge Funds, Global Opportunity [Member] | Foreign Plan [Member]
Asset allocations	29.00%	37.00%
Other Debt Obligations [Member] | UNITED STATES
Asset allocations	10.00%	10.00%
Other Debt Obligations [Member] | Foreign Plan [Member]
Asset allocations	2.00%	2.00%