Pension Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Components of net periodic pension cost (benefit)
Service cost	$ 158	$ 165
Interest cost	1,333	1,531
Expected return on plan assets	(2,649)	(2,946)
Amortization of actuarial loss	1,140	1,001
Administrative expenses	89	86
Net pension cost (benefit)	$ 71	$ (163)