EMPLOYEE BENEFIT PLANS (Tables)

6 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Components of Net Periodic Cost

The components of the net periodic cost for pension benefits, including the Company's Pension Equalization Plan, and OPEB costs (principally health care and life insurance) for employees and covered dependents were as follows:

	Pension								OPEB
	Three Months Ended				Six Months Ended				Three Months Ended				Six Months Ended
	March 31,				March 31,				March 31,				March 31,
(Thousands)	2021		2020		2021		2020		2021		2020		2021		2020
Service cost	$	2,183	$	2,055	$	4,365	$	4,111	$	1,211	$	1,072	$	2,422	$	2,427
Interest cost	2,278		2,646		4,556		5,293		1,517		1,509		3,035		3,513
Expected return on plan assets	(4,851)		(5,232)		(10,075)		(10,289)		(1,565)		(1,695)		(3,248)		(3,255)
Recognized actuarial loss	2,861		2,466		5,723		5,212		1,978		930		3,955		3,721
Prior service cost (credit) amortization	26		26		51		51		(45)		(50)		(90)		(99)
Net periodic benefit cost	$	2,497	$	1,961	$	4,620	$	4,378	$	3,096	$	1,766	$	6,074	$	6,307