Defined Benefit Pension Plan (Tables)

6 Months Ended

Jun. 30, 2017

Defined Benefits Pension Plan [Abstract]

Net Pension Costs

	Six Months Ended				Three Months Ended
	June 30,				June 30,
	2017		2016		2017		2016
	(in thousands)
Service cost plus expected expenses and net of
expected plan participant contributions	$	607	$	572	$	303	$	286
Interest cost		795		792		397		396
Expected return on plan assets		(1,470)		(1,477)		(734)		(738)
Amortization of net actuarial loss		9		122		4		61
Net pension cost (credit)	$	(59)	$	9	$	(30)	$	5