Note 12 - Retirement Benefits - Contributions to Defined Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Contributions to defined benefit plans	$ 4,828	$ 1,719	$ 4,880	$ 1,959
Remaining contributions to be made	5,222		5,222
UNITED STATES | Defined Benefit Plan, Funded Plan [Member]
Contributions to defined benefit plans	4,776	1,468	4,776	1,468
Remaining contributions to be made	4,748		4,748
UNITED STATES | Defined Benefit Plan, Unfunded Plan [Member]
Contributions to defined benefit plans	52	58	104	114
Remaining contributions to be made	107		107
UNITED KINGDOM
Contributions to defined benefit plans	0	193	0	377
Remaining contributions to be made	0		0
GERMANY | Defined Benefit Plan, Unfunded Plan [Member]
Contributions to defined benefit plans	0	0	0	0
Remaining contributions to be made	297		297
IRELAND
Contributions to defined benefit plans	0	$ 0	0	$ 0
Remaining contributions to be made	$ 70		$ 70