Note 6 - Pension and Post-retirement Benefits (Details) - Net Periodic Benefit Costs for Postretirement Medical Plan (Postretirement Medical and Life Insurance Plan [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Postretirement Medical and Life Insurance Plan [Member]
Note 6 - Pension and Post-retirement Benefits (Details) - Net Periodic Benefit Costs for Postretirement Medical Plan [Line Items]
Service cost	$ 25	$ 127	$ 202	$ 383
Interest cost	66	136	331	409
Amortization of prior service credit	(260)	(185)	(511)	(557)
Amortization of accumulated loss	(1)	40	(1)	119
	$ (170)	$ 118	$ 21	$ 354