Employee Retirement and Pension Benefits - Components of Pension Benefit/ Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
U.S.
Defined Benefit Plan Disclosure
Service cost	$ 4,890	$ 4,170	$ 3,870
Interest cost	14,861	13,180	13,371
Expected return on plan assets	(18,622)	(20,769)	(17,940)
Amortization of net actuarial pension loss	8,919	9,314	12,680
Pension benefit expense	$ 10,048	$ 5,895	$ 11,981
Discount rate, percent	4.27%	3.47%	3.94%
Expected long-term rate of return on assets, percent	6.25%	6.25%	6.25%
Non U.S
Defined Benefit Plan Disclosure
Service cost	$ 2,386	$ 2,070	$ 1,668
Interest cost	1,398	1,417	1,272
Expected return on plan assets	(589)	(833)	(700)
Amortization of net actuarial pension loss	225	189	145
Pension benefit expense	$ 3,420	$ 2,843	$ 2,385
Minimum | Non U.S
Defined Benefit Plan Disclosure
Discount rate, percent	0.60%	0.20%	0.80%
Expected long-term rate of return on assets, percent	0.00%	0.00%	0.00%
Compensation increase rate, percent	0.50%	0.50%	0.50%
Maximum | Non U.S
Defined Benefit Plan Disclosure
Discount rate, percent	8.50%	9.00%	7.20%
Expected long-term rate of return on assets, percent	5.80%	5.30%	5.70%
Compensation increase rate, percent	7.00%	7.00%	7.00%