Note 8 - Pension Benefits

Pension Plans

The Company has a non-contributory defined benefit pension plan covering employees who meet age and service requirements (the “Qualified Pension Plan”). The Company also has a supplemental non-contributory pension plan covering certain management employees (the “Nonqualified Pension Plan” and together with the Qualified Pension Plan, the “Pension Plans”). Effective as of January 1, 2016, the Company froze the Pension Plans to new participants, and employees eligible to participate in the Pension Plans prior to them being frozen will continue to earn benefits.

Components of Net Periodic Benefit Cost for the Pension Plans

The following table presents the components of the net periodic benefit cost for the Pension Plans:



	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2018			2017			2018			2017
	(in thousands)
Service cost	$	1,705		$	1,269		$	3,365		$	3,319
Interest cost	637			617			1,310			1,344
Expected return on plan assets that reduces periodic pension benefit cost	(370		)	(563		)	(931		)	(1,122		)
Amortization of prior service cost	5			5			9			9
Amortization of net actuarial loss	340			253			664			649
Net periodic benefit cost	$	2,317		$	1,581		$	4,417		$	4,199

Prior service costs are amortized on a straight-line basis over the average remaining service period of active participants. Gains and losses in excess of 10 percent of the greater of the benefit obligation or the market-related value of assets are amortized over the average remaining service period of active participants. As a result of the adoption of ASU 2017-07, the service cost component of net periodic benefit cost for the Pension Plans is presented as an operating expense within the general and administrative and exploration expense line items on the accompanying statements of operations while the other components of net periodic benefit cost for the Pension Plans are presented as non-operating expenses within the other non-operating income, net line item on the accompanying statements of operations. Please refer to Note 1 - Summary of Significant Accounting Policies for further detail.

Contributions

The Company contributed $6.1 million to the Qualified Pension Plan during the six months ended June 30, 2018.