GOODWILL AND OTHER INTANGIBLE ASSETS Balances and Changes in Carrying Amounts of Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 543,903	$ 527,150
Divestiture	0	(3,316)
Impairment	(104,461)	(7,169)
Translation	(9,624)	27,238
Goodwill, ending balance	429,818	543,903
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, beginning balance	126,771
Cumulative goodwill impairment charges, ending balance	231,232	126,771
United States [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	191,535	202,020
Divestiture	0	(3,316)
Impairment	0	(7,169)
Translation	0	0
Goodwill, ending balance	191,535	191,535
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, beginning balance	24,207
Cumulative goodwill impairment charges, ending balance	24,207	24,207
Canada [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	130,422	122,140
Divestiture	0	0
Impairment	0	0
Translation	(3,304)	8,282
Goodwill, ending balance	127,118	130,422
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, beginning balance	32,265
Cumulative goodwill impairment charges, ending balance	32,265	32,265
Other Businesses [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	221,946	202,990
Divestiture	0	0
Impairment	(104,461)	0
Translation	(6,320)	18,956
Goodwill, ending balance	111,165	221,946
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, beginning balance	70,299
Cumulative goodwill impairment charges, ending balance	$ 174,760	$ 70,299

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Section 45
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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