EMPLOYEE BENEFIT PLANS - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Employee benefit plans
Service cost	$ 22,159	$ 34,847	$ 35,055
Interest cost	34,190	25,596	21,667
Expected return on plan assets	(53,684)	(45,228)	(39,472)
Net amortization and deferral	(3,043)	5,781	10,003
Net periodic (income) cost	(378)	20,996	27,253
Other Benefits
Employee benefit plans
Service cost	4,489	6,830	6,072
Interest cost	5,219	4,009	3,217
Expected return on plan assets	(10,543)	(9,927)	(8,769)
Net amortization and deferral	(2,019)	(824)	(293)
Net periodic (income) cost	$ (2,854)	$ 88	$ 227