Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Pension Benefits [Member]
Components of net periodic cost:
Service cost	$ 11	$ 31	$ 33	$ 93
Interest cost	174	182	522	549
Expected return on plan assets	(133)	(118)	(399)	(355)
Recognized net actuarial loss (gain)	46	106	138	318
Amortization of prior service cost	0	7	0	21
Net periodic cost (benefit)	98	208	294	626
Postretirement Health Coverage [Member]
Components of net periodic cost:
Service cost	4	5	12	14
Interest cost	13	13	39	39
Expected return on plan assets	0	0	0	0
Recognized net actuarial loss (gain)	(30)	(39)	(90)	(116)
Amortization of prior service cost	(92)	(92)	(276)	(276)
Net periodic cost (benefit)	$ (105)	$ (113)	$ (315)	$ (339)