Pensions (Tables)

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The following table summarizes the components of net periodic pension cost under the Dutch Plan (in thousands):

	Three Months Ended
	March 31,
	2018			2017
Service cost	$	349		$	375
Interest cost	300			275
Expected return on plan assets	(259		)	(233		)
Amortization of prior service cost	(21		)	(19		)
Amortization of actuarial loss	84			111
Net periodic pension cost	$	453		$	509