EMPLOYEE BENEFIT PLANS (Tables)

6 Months Ended

Mar. 31, 2019

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

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)	2019			2018			2019			2018			2019			2018			2019			2018
Service cost	$	1,846		$	2,034		$	3,691		$	4,069		$	1,101		$	1,151		$	2,202		$	2,303
Interest cost	3,043			2,624			6,086			5,247			2,081			1,591			4,162			3,182
Expected return on plan assets	(4,764		)	(4,909		)	(9,527		)	(9,819		)	(1,379		)	(1,338		)	(2,758		)	(2,676		)
Recognized actuarial loss	1,441			1,885			2,882			3,769			1,616			1,165			3,233			2,330
Prior service cost amortization	26			26			51			53			(91		)	(91		)	(182		)	(182		)
Net periodic benefit cost	$	1,592		$	1,660		$	3,183		$	3,319		$	3,328		$	2,478		$	6,657		$	4,957