Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Pension Benefits [Member]
Components of net periodic cost:
Service cost	$ 23	$ 24	$ 46	$ 48
Interest cost	216	224	432	448
Expected return on plan assets	(123)	(124)	(246)	(248)
Recognized net actuarial (gain) loss	229	140	457	280
Amortization of prior service cost	21	22	43	44
Net periodic cost	366	286	732	572
Retiree Health Care Benefits [Member]
Components of net periodic cost:
Service cost	6	13	12	26
Interest cost	19	24	38	48
Expected return on plan assets	0	0	0	0
Recognized net actuarial (gain) loss	(53)	(22)	(106)	(44)
Amortization of prior service cost	(68)	(68)	(136)	(136)
Net periodic cost	$ (96)	$ (53)	$ (192)	$ (106)