RETIREMENT AND DEFERRED COMPENSATION PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
United States
Components of net periodic benefit cost:
Service cost	$ 3,570	$ 2,772	$ 10,709	$ 8,320
Interest cost	1,761	1,845	5,284	5,536
Expected return on plan assets	(3,062)	(3,095)	(9,186)	(9,284)
Amortization of net loss	1,422	490	4,264	1,468
Amortization of prior service cost	0	0	0	0
Net periodic benefit cost	3,691	2,012	11,071	6,040
Foreign Plans
Components of net periodic benefit cost:
Service cost	1,867	1,429	5,402	4,334
Interest cost	360	491	1,040	1,487
Expected return on plan assets	(671)	(581)	(1,936)	(1,759)
Amortization of net loss	544	356	1,572	1,078
Amortization of prior service cost	101	111	293	337
Net periodic benefit cost	$ 2,201	$ 1,806	$ 6,371	$ 5,477