GOODWILL AND OTHER INTANGIBLE ASSETS Balances and Changes in Carrying Amounts of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 527,150	$ 582,336
Purchase Price Adjustments		8,362
Divestiture	(3,316)
Impairment	(7,169)	(47,244)
Translation	27,238	(16,304)
Goodwill, ending balance	543,903	527,150
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2017	119,602
Cumulative goodwill impairment charges, December 31, 2017	126,771	119,602
United States
Goodwill [Roll Forward]
Goodwill, beginning balance	202,020	202,020
Purchase Price Adjustments		0
Divestiture	(3,316)
Impairment	(7,169)	0
Translation	0	0
Goodwill, ending balance	191,535	202,020
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2017	17,038
Cumulative goodwill impairment charges, December 31, 2017	24,207	17,038
Canada
Goodwill [Roll Forward]
Goodwill, beginning balance	122,140	118,529
Purchase Price Adjustments		0
Divestiture	0
Impairment	0	0
Translation	8,282	3,611
Goodwill, ending balance	130,422	122,140
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2017	32,265
Cumulative goodwill impairment charges, December 31, 2017	32,265	32,265
Other Businesses [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	202,990	261,787
Purchase Price Adjustments		8,362
Divestiture	0
Impairment	0	(47,244)
Translation	18,956	(19,915)
Goodwill, ending balance	221,946	202,990
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Cumulative goodwill impairment charges, January 1, 2017	70,299
Cumulative goodwill impairment charges, December 31, 2017	$ 70,299	$ 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
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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

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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
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-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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-Publisher FASB
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-Topic 350
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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