PENSION AND OTHER POST-RETIREMENT BENEFIT PLANS - SCHEDULE OF COMPONENTS OF NET PERIODIC BENEFIT COST (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits
Amounts recognized in net periodic benefit cost
Service cost	$ 13,897	$ 15,323	$ 14,991
Interest cost	35,877	38,675	41,205
Expected return on plan assets	(48,178)	(51,193)	(48,978)
Amortization of prior service credit	(3,558)	(5,493)	(5,658)
Amortization of net (gain) loss	12,793	15,248	19,846
Curtailment credit	0	0	0
Settlement loss	12,443	14,894	15,254
Total net periodic benefit cost	23,274	27,454	36,660
Change in plan assets and benefit obligations recognized in AOCI, pre-tax
Actuarial net (gain) loss	(42,728)	(15,513)	(32,720)
Prior service cost (credit)	3,559	5,436	5,670
Total recognized in other comprehensive (income) loss, pre-tax	(39,169)	(10,077)	(27,050)
Net amounts recognized in periodic benefit cost and AOCI	(15,895)	17,377	9,610
Other Benefits
Amounts recognized in net periodic benefit cost
Service cost	114	131	221
Interest cost	4,928	4,852	7,171
Expected return on plan assets	0	0	0
Amortization of prior service credit	(387)	(151)	(50)
Amortization of net (gain) loss	1,254	557	(966)
Curtailment credit	0	0	(740)
Settlement loss	0	0	926
Total net periodic benefit cost	5,909	5,389	6,562
Change in plan assets and benefit obligations recognized in AOCI, pre-tax
Actuarial net (gain) loss	19,535	4,609	38,698
Prior service cost (credit)	382	(963)	(736)
Total recognized in other comprehensive (income) loss, pre-tax	19,917	3,646	37,962
Net amounts recognized in periodic benefit cost and AOCI	$ 25,826	$ 9,035	$ 44,524