PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Tables)

6 Months Ended

Mar. 31, 2013

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)	2013			2012			2013			2012
Service cost – benefits earned during the period	$	2,311		$	2,301		$	4,622		$	4,613
Interest cost on projected benefit obligation	4,066			4,840			8,132			9,711
Expected return on plan assets	(4,741		)	(4,899		)	(9,482		)	(9,798		)
Amortization of prior service cost	136			148			272			296
Amortization of actuarial loss	2,839			2,259			5,678			4,536
Loss on lump-sum settlement	—			3,407			—			3,407
Sub-total	4,611			8,056			9,222			12,765
Regulatory adjustment	(433		)	(484		)	(867		)	(967		)
Net pension cost	$	4,178		$	7,572		$	8,355		$	11,798

Net periodic postretirement benefit costs consisted of the following components:

	Three Months Ended March 31,						Six Months Ended March 31,
(Thousands)	2013			2012			2013			2012
Service cost-benefits earned during the period	$	2,534		$	2,015		$	5,067		$	4,030
Interest cost on accumulated       postretirement benefit obligation	1,279			1,380			2,558			2,760
Expected return on plan assets	(1,081		)	(991		)	(2,162		)	(1,982		)
Amortization of transition obligation	23			34			46			68
Amortization of prior service cost (credit)	1			(518		)	2			(1,036		)
Amortization of actuarial loss	1,325			1,065			2,650			2,130
Sub-total	4,081			2,985			8,161			5,970
Regulatory adjustment	(1,699		)	(604		)	(3,398		)	(1,208		)
Net postretirement benefit cost	$	2,382		$	2,381		$	4,763		$	4,762