PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Tables)

6 Months Ended

Mar. 31, 2014

Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]

Net Periodic Cost

The net periodic pension costs include the following components:

	Three Months Ended March 31,						Six Months Ended March 31,
(Thousands)	2014			2013			2014			2013
Service cost – benefits earned during the period	$	2,428		$	2,311		$	4,856		$	4,622
Interest cost on projected benefit obligation	6,010			4,066			12,020			8,132
Expected return on plan assets	(6,645		)	(4,741		)	(13,290		)	(9,482		)
Amortization of prior service cost	125			136			249			272
Amortization of actuarial loss	1,772			2,839			3,544			5,678
Loss on lump-sum settlement	1,319			—			1,319			—
Sub-total	5,009			4,611			8,698			9,222
Regulatory adjustment	1,571			(433		)	4,461			(867		)
Net pension cost	$	6,580		$	4,178		$	13,159		$	8,355

Net periodic postretirement benefit costs consisted of the following components:

	Three Months Ended March 31,						Six Months Ended March 31,
(Thousands)	2014			2013			2014			2013
Service cost - benefits earned during the period	$	2,804		$	2,534		$	5,608		$	5,067
Interest cost on accumulated postretirement benefit obligation	2,170			1,279			4,339			2,558
Expected return on plan assets	(1,709		)	(1,081		)	(3,418		)	(2,162		)
Amortization of transition obligation	—			23			—			46
Amortization of prior service cost (credit)	(1		)	1			(2		)	2
Amortization of actuarial loss	1,505			1,325			3,010			2,650
Sub-total	4,769			4,081			9,537			8,161
Regulatory adjustment	(2,388		)	(1,699		)	(4,775		)	(3,398		)
Net postretirement benefit cost	$	2,381		$	2,382		$	4,762		$	4,763