Employee Retirement and Pension Benefits - Change in Projected Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
U.S.
Defined Benefit Plan, Change in Benefit Obligation
Balance as of January 1,	$ 383,936	$ 435,696
Service cost	4,890	4,170
Interest cost	14,861	13,180
Actuarial loss	51,434	(48,463)
Benefits paid	(16,751)	(15,965)
Administrative expenses paid	(4,962)	(4,682)
Balance at period end	$ 433,408	$ 383,936
Discount rate, percentage	3.31%	4.27%
Non U.S
Defined Benefit Plan, Change in Benefit Obligation
Balance as of January 1,	$ 42,803	$ 41,406
Pension obligation acquired	0	4,891
Service cost	2,655	2,242
Interest cost	1,405	956
Actuarial loss	6,084	776
Benefits paid	(5,240)	(4,481)
Administrative expenses paid	(21)	(25)
Cumulative translation adjustment	21	(2,962)
Balance at period end	$ 47,707	$ 42,803
Non U.S | Minimum
Defined Benefit Plan, Change in Benefit Obligation
Discount rate, percentage	0.60%	0.20%
Compensation increase rate, percentage	0.50%	0.50%
Non U.S | Maximum
Defined Benefit Plan, Change in Benefit Obligation
Discount rate, percentage	8.50%	9.00%
Compensation increase rate, percentage	7.00%	7.00%