EMPLOYEE BENEFIT PLANS (Tables)

3 Months Ended

Dec. 31, 2016

Compensation and Retirement Disclosure [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						Three Months Ended
	December 31,						December 31,
(Thousands)	2016			2015			2016			2015
Service cost	$	2,087		$	1,898		$	1,095		$	1,130
Interest cost	2,443			2,836			1,386			1,564
Expected return on plan assets	(4,828		)	(5,029		)	(1,192		)	(1,211		)
Recognized actuarial loss	2,207			1,820			1,093			819
Prior service cost amortization	27			28			(91		)	(91		)
Net periodic benefit cost	$	1,936		$	1,553		$	2,291		$	2,211