Benefit Plans (Tables)

9 Months Ended

Sep. 29, 2018

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The components of net periodic benefit cost for the three and nine months ended September 29, 2018 and September 30, 2017 were as follows: 

	For the Three Months Ended						For the Nine Months Ended
(in thousands)	September 29, 2018			September 30, 2017			September 29, 2018			September 30, 2017
Components of net periodic benefit cost:
Service cost	$	533		$	408		$	1,599		$	1,224
Interest cost	501			360			1,503			1,080
Expected return on plan assets	(540		)	(476		)	(1,620		)	(1,428		)
Amortization of prior service	74			84			222			252
Net periodic benefit cost	$	568		$	376		$	1,704		$	1,128