REMEDIAL LIABILITIES (Anticipated Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accrual for Environmental Loss Contingencies, Net [Abstract]
2020	$ 16,729
2021	17,883
2022	9,207
2023	7,930
2024	5,701
Thereafter	77,000
Undiscounted remedial liabilities	134,450
Less: Discount	(20,277)
Total remedial liabilities	$ 114,173	$ 121,017	$ 124,468

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of imputed interest necessary to reduce (reconcile) the undiscounted amount of the accrual for environmental loss contingencies to the present value.

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Undiscounted amount of the accrual for environmental loss contingencies.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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