Benefit Plans

The Corporation sponsors several qualified and nonqualified pension and other postretirement plans for certain of its employees. The net periodic pension cost is based on estimated values provided by an outside actuary. The components of net periodic benefit cost are as follows:



	Pension Benefits
	Three Months Ended March 31,
(In thousands)	2016			2015
Service cost	$	198		$	207
Interest cost	3,649			3,517
Expected return on assets	(3,788		)	(3,902		)
Amortization of unrecognized prior service costs	75			570
Amortization of actuarial losses/(gains)	830			1,057
Net periodic pension cost	$	964		$	1,449



	Postretirement Benefits
	Three Months Ended March 31,
(In thousands)	2016			2015
Service cost	$	26		$	41
Interest cost	64			144
Amortization of unrecognized prior service costs	(636		)	(160		)
Amortization of actuarial losses/(gains)	245			81
Net periodic postretirement cost	$	(301	)	$	106

For further information on the Corporation's employee benefit plans, refer to Note 13 (Benefit Plans) to the consolidated financial statements in the 2015 Form 10-K.