BENEFIT PLANS (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) entity	Mar. 31, 2020 USD ($)
BENEFIT PLANS [Abstract]
Number of funded, noncontributory defined benefit pension plans	2
Number of unfunded, nonqualified pension plans	3
Number of defined contribution plans	2
Normal retirement age	65 years
Expense recognized related to defined contribution plans | $	$ 22,137	$ 11,057