Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Pension Benefits [Member]
Components of net periodic cost:
Service cost	$ 31	$ 23
Interest cost	173	216
Expected return on plan assets	(115)	(123)
Recognized net actuarial (gain) loss	218	228
Amortization of prior service cost	22	22
Net periodic cost	329	366
Postretirement Health Coverage [Member]
Components of net periodic cost:
Service cost	7	6
Interest cost	16	19
Expected return on plan assets	0	0
Recognized net actuarial (gain) loss	(45)	(53)
Amortization of prior service cost	(68)	(68)
Net periodic cost	$ (90)	$ (96)