Defined Benefit Pension Plans

We sponsor both funded and unfunded defined benefit pension plans offering death and disability, retirement, and special termination benefits for our international employees, primarily in Germany, France, Italy, Indonesia, Brazil, and Spain. The defined benefit obligation is calculated annually by using the projected unit credit method. The measurement date for the pension plans was December 31, 2017.

Amounts recognized on the Consolidated Balance Sheets consist of:



	March 31, 2018		December 31, 2017
	(in thousands)
Assets
Plan assets in other long-term assets	$	1,054	$	991

Liabilities
Current portion of pension benefit obligation in wages and benefits payable	3,291		3,260
Long-term portion of pension benefit obligation	100,045		95,717

Pension benefit obligation, net	$	102,282	$	97,986

Our asset investment strategy focuses on maintaining a portfolio using primarily insurance funds, which are accounted for as investments and measured at fair value, in order to achieve our long-term investment objectives on a risk adjusted basis. Our general funding policy for these qualified pension plans is to contribute amounts sufficient to satisfy regulatory funding standards of the respective countries for each plan.

Net periodic pension benefit costs for our plans include the following components:



	Three Months Ended March 31,
	2018			2017
	(in thousands)
Service cost	$	1,049		$	928
Interest cost	609			525
Expected return on plan assets	(181		)	(146		)
Amortization of actuarial net loss	403			391
Amortization of unrecognized prior service costs	17			15
Net periodic benefit cost	$	1,897		$	1,713