Retirement Plans - Schedule of Changes in Projected Benefit Obligation and Plan Assets, and Net Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Company contributions	$ 800
United States [Member]
Benefit obligation, beginning of year	63,700	$ 64,900
Interest cost	2,100	2,500
Actuarial (gain) loss	(2,000)	2,500
Benefits paid	(2,500)	(2,500)
Settlement payments	(1,800)	(3,700)
Foreign exchange rate changes
Projected benefit obligation, end of year	59,600	63,700
Fair value of plan assets, beginning of year	48,800	49,800
Actual return on plan assets	(2,200)	4,800
Foreign exchange rate changes
Company contributions		400
Benefits paid	(2,500)	(2,500)
Settlement payments	(1,800)	(3,700)
Fair value of plan assets, end of year	43,100	48,800
Funded status of the plan, end of year	(16,500)	(14,900)
Foreign Plan [Member]
Benefit obligation, beginning of year	26,800	24,100
Interest cost	400	400
Actuarial (gain) loss	(300)	(100)
Benefits paid	(1,000)	(1,000)
Settlement payments
Foreign exchange rate changes	(1,300)	3,400
Projected benefit obligation, end of year	24,600	26,800
Fair value of plan assets, beginning of year	17,500	15,200
Actual return on plan assets	300	1,100
Foreign exchange rate changes	(800)	2,100
Company contributions		100
Benefits paid	(1,000)	(1,000)
Settlement payments
Fair value of plan assets, end of year	16,000	17,500
Funded status of the plan, end of year	$ (8,600)	$ (9,300)