RETIREMENT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
RETIREMENT PLANS
Interest cost	$ 616	$ 875	$ 2,264	$ 2,626
Expected return on assets	(1,067)	(1,086)	(3,149)	(3,259)
Actuarial loss	(715)	(487)	(1,801)	(1,461)
Net periodic benefit cost	$ 264	$ 276	$ 916	$ 828