Retirement and Other Emplyee Benefits (Tables)

9 Months Ended

Sep. 30, 2015

Retirement and Other Employee Benefits

Schedule of net periodic benefit pension cost

Net periodic 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 September 30,
	Pension Benefits						SERP						OPEB
	2015			2014			2015			2014			2015			2014
Service cost	$	1,816		$	1,596		$	33		$	57		$	945		$	737
Interest cost	2,702			2,648			102			117			1,175			1,109
Expected return on plan assets	(3,396		)	(3,185		)	—			—			(1,272		)	(1,207		)
Amortization of prior service cost (1)	(157		)	105			(10		)	(2		)	(253		)	(253		)
Amortization of net actuarial loss (1)	2,835			1,660			168			168			699			268
Net periodic benefit cost	$	3,800		$	2,824		$	293		$	340		$	1,294		$	654

	Nine months ended September 30,
	Pension Benefits						SERP						OPEB
	2015			2014			2015			2014			2015			2014
Service cost	$	5,581		$	4,850		$	119		$	115		$	2,785		$	1,950
Interest cost	7,708			8,114			286			290			3,502			3,270
Expected return on plan assets	(10,175		)	(9,829		)	—			—			(3,897		)	(3,600		)
Amortization of prior service cost (1)	(472		)	314			(32		)	(6		)	(758		)	(758		)
Amortization of net actuarial loss (1)	7,525			4,958			448			378			2,061			725
Net periodic benefit cost	$	10,167		$	8,407		$	821		$	777		$	3,693		$	1,587

	Twelve months ended September 30,
	Pension Benefits						SERP						OPEB
	2015			2014			2015			2014			2015			2014
Service cost	$	7,198		$	6,713		$	157		$	148		$	3,435		$	2,686
Interest cost	10,413			10,631			383			370			4,592			4,226
Expected return on plan assets	(13,452		)	(12,936		)	—			—			(5,097		)	(4,689		)
Amortization of prior service cost (1)	(368		)	447			(34		)	(8		)	(1,011		)	(1,011		)
Amortization of net actuarial loss (1)	9,178			7,569			574			520			2,303			1,291
Net periodic benefit cost	$	12,969		$	12,424		$	1,080		$	1,030		$	4,222		$	2,503

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