EMPLOYEE BENEFIT PLANS - Funded status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Supplemental Benefit Plan
Change in benefit obligations
Benefit obligations at beginning of period	$ 358	$ 338
Interest cost	15	16	$ 7
Actuarial (gain) loss	(5)	4
Benefit obligations at end of period	368	358	338
Change in plan assets
Funded status at period end	(368)	(358)
Accumulated benefit obligation	368	358
Postretirement Health Benefit Plan
Change in benefit obligations
Benefit obligations at beginning of period	13,668	12,534
Service cost	60	78	156
Interest cost	632	599	441
Actuarial (gain) loss	162	1,137
Benefits paid	(697)	(680)
Benefit obligations at end of period	13,825	13,668	$ 12,534
Change in plan assets
Employer contributions	697	680
Benefits paid	(697)	(680)
Funded status at period end	(13,825)	(13,668)
Accumulated benefit obligation	$ 13,825	$ 13,668