EMPLOYEE BENEFITS (AOCI) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Unrecognized prior service cost	$ (32,175)	$ 0
Unrecognized actuarial (gain) loss	66,864	64,059
Total amounts recognized in AOCI	34,689	64,059
Anticipated amortization of net actuarial losses in next fiscal year	3,995
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Unrecognized prior service cost	(20,863)	(28,947)
Unrecognized actuarial (gain) loss	6,627	8,086
Total amounts recognized in AOCI	(14,236)	$ (20,861)
Anticipated amortization of net actuarial losses in next fiscal year	$ 260

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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