EMPLOYEE BENEFIT PLANS - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits
Employee benefit plans
Service cost	$ 35,055	$ 36,002	$ 26,718
Interest cost	21,667	25,741	26,966
Expected return on plan assets	(39,472)	(33,086)	(30,285)
Net amortization and deferral	10,003	17,027	10,975
Net periodic benefit cost	27,253	45,684	34,374
Other Benefits
Employee benefit plans
Service cost	6,072	7,945	7,475
Interest cost	3,217	4,305	5,441
Expected return on plan assets	(8,769)	(7,236)	(5,794)
Net amortization and deferral	(293)	197	758
Net periodic benefit cost	$ 227	$ 5,211	$ 7,880