REMEDIAL LIABILITIES (Anticipated Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accrual for Environmental Loss Contingencies, Net [Abstract]
2019	$ 13,975
2020	15,467
2021	14,593
2022	9,560
2023	8,688
Thereafter	81,453
Undiscounted remedial liabilities	143,736
Less: Discount	(22,719)
Total remedial liabilities	$ 121,017	$ 124,468	$ 128,007

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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