Pension Benefits (Tables)

3 Months Ended

Mar. 31, 2018

Defined Benefit Plan [Abstract]

Components of the net periodic benefit cost for the Pension Plans [Table Text Block]

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

	For the Three Months Ended   March 31,
	2018			2017
	(in thousands)
Service cost	$	1,660		$	2,050
Interest cost	673			727
Expected return on plan assets that reduces periodic pension benefit cost	(561		)	(559		)
Amortization of prior service cost	4			4
Amortization of net actuarial loss	324			396
Net periodic benefit cost	$	2,100		$	2,618