Note 6 - Pensions and Post-retirement Benefits - Net Periodic Benefit Costs for Postretirement Medical Plan (Details) - Post Retirement Medical and Life Insurance Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Service cost	$ 23	$ 26
Interest cost	68	72
Amortization of prior service credit	(168)	(195)
Amortization of net loss	30	4
	$ (47)	$ (93)