RETIREMENT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Pension Plan
Net periodic benefit cost:
Service cost	$ 41	$ 54	$ 141	$ 162
Interest cost	92	88	279	266
Expected return on plan assets	(165)	(147)	(486)	(443)
Amortization of prior service cost (credit)	2	2	5	5
Amortization of net actuarial loss (gain)	(3)	25	1	74
Net periodic benefit (income) cost	(33)	22	(60)	64
Other disclosures
Contribution by the entity to the Pension Plan			115
SERP
Net periodic benefit cost:
Service cost	6	10	24	30
Interest cost	16	19	58	57
Amortization of prior service cost (credit)	(2)	(1)	(4)	(4)
Amortization of net actuarial loss (gain)	(1)	3	1	10
Net periodic benefit (income) cost	19	31	79	93
Postretirement Medical
Net periodic benefit cost:
Service cost	0	0	0	0
Interest cost	25	19	75	57
Amortization of prior service cost (credit)	0	0	0	0
Amortization of net actuarial loss (gain)	13	2	39	8
Net periodic benefit (income) cost	$ 38	$ 21	$ 114	$ 65