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		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Service cost	$ 24	$ 27	$ 47	$ 53
Interest cost	68	72	136	144
Amortization of prior service credit	(169)	(196)	(337)	(391)
Amortization of net loss	30	3	60	7
	$ (47)	$ (94)	$ (94)	$ (187)