Retirement Benefits

3 Months Ended

Mar. 31, 2012

Retirement Benefits

Retirement Benefits

Note 8 — Retirement Benefits

Net retirement benefit cost, some of which is capitalized as a component of labor cost and some of which is deferred as a regulatory asset, is comprised of the following components and is shown for our noncontributory defined benefit pension plan, our supplemental retirement program (SERP) and other postretirement benefits (OPEB) (in thousands):

	Three months ended March 31,
	Pension						SERP						OPEB
	2012			2011			2012			2011			2012			2011
Service cost	$	1,628		$	1,393		$	7		$	20		$	565		$	626
Interest cost	2,551			2,591			56			41			1,032			1,130
Expected return on plan assets	(3,076		)	(2,680		)	—			—			(1,041		)	(1,050		)
Amortization of prior service cost (1)	133			133			(2		)	(2		)	(253		)	(253		)
Amortization of net actuarial loss (1)	1,950			1,353			76			33			468			500
Net periodic benefit cost	$	3,186		$	2,790		$	137		$	92		$	771		$	953

	Twelve months ended March 31,
	Pension						SERP						OPEB
	2012			2011			2012			2011			2012			2011
Service cost	$	5,830		$	5,007		$	81		$	73		$	2,205		$	2,254
Interest cost	10,366			10,156			198			155			4,286			4,396
Expected return on plan assets	(11,534		)	(10,044		)	—			—			(4,148		)	(3,927		)
Amortization of prior service cost (1)	532			531			(8		)	(8		)	(1,011		)	(1,011		)
Amortization of net actuarial loss (1)	6,091			4,315			213			98			1,729			1,655
Net periodic benefit cost	$	11,285		$	9,965		$	484		$	318		$	3,061		$	3,367

(1) Amounts are amortized from our regulatory asset originally recorded upon recognizing our net pension liability on the balance sheet.

In accordance with our regulatory agreements, our funding policy is to make contributions that are at least equal to the greater of either the minimum funding requirements of ERISA or the accrued cost of the plan. We have contributed $5.1 million to our Pension Trust in 2012 and expect our remaining 2012 contribution to be approximately $6.0 million. The actual minimum funding requirements will be determined based on the results of the actuarial valuations. Our OPEB funding policy is to contribute annually an amount at least equal to the actuarial cost of postretirement benefits.