INVENTORIES AND SUPPLIES (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Oil and oil products	$ 68,125	$ 58,142
Supplies and drums	100,118	94,242
Solvent and solutions	9,230	9,167
Modular camp accommodations	2,494	1,826
Other	13,577	12,635
Total inventories and supplies	$ 193,544	$ 176,012

Energy Related Inventory Modular Camp Accommodations

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- Definition

Energy Related Inventory and Supplies Other

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- Definition

Energy Related Inventory Supplies and Drums

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- Definition

Carrying amount as of the balance sheet date of solvents or substances produced by or used in a process to change the shape, form or composition of some related matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of consideration paid in advance for supplies that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (g)(7)
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-Topic 210
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-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6787-107765

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