Note 8 - Pension and Post-retirement Benefits (Details Textual) $ in Millions	6 Months Ended
Dec. 31, 2018 USD ($)
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	$ 3.1
Pension Plan [Member] \| UNITED STATES
Defined Benefit Plan, Plan Assets, Contributions by Employer	1.8
Pension Plan [Member] \| UNITED KINGDOM
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0.5

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

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-Publisher FASB
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Name:	us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration