EMPLOYEE BENEFIT PLANS - Expected Benefit Payments, Net (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Other Benefits
Expected Benefit Payments Before Medicare Part D Subsidy
2022	$ 3,485
2023	3,854
2024	4,328
2025	4,577
2026	4,840
2027-2031	28,931
Total payments	50,015
Effect of Medicare Part D Subsidy on Expected Benefit Payments
2022	(254)
2023	(279)
2024	(300)
2025	(332)
2026	(364)
2027-2031	(2,286)
Total payments	(3,815)
Expected Benefit Payments Net of Medicare Part D Subsidy
2022	3,485
2023	3,854
2024	4,328
2025	4,577
2026	4,840
2027-2031	28,931
Postretirement Health Coverage
Expected Benefit Payments Before Medicare Part D Subsidy
2022	3,231
2023	3,575
2024	4,028
2025	4,245
2026	4,476
2027-2031	26,645
Expected Benefit Payments Net of Medicare Part D Subsidy
2022	3,231
2023	3,575
2024	4,028
2025	4,245
2026	4,476
2027-2031	26,645
Total payments	$ 46,200

Defined Benefit Plan, Expected Future Benefit Payment, Net Prescription Drug Subsidy Receipts [Abstract]

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