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GOODWILL AND INTANGIBLE ASSETS - Schedule of Activity and Balances Related to Goodwill by Reporting Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 162,734	$ 122,605
Acquisitions	25,704	40,129
Other	(2,619)
Goodwill, ending balance	185,819	162,734
Eastern
Goodwill [Roll Forward]
Goodwill, beginning balance	28,154	19,192
Acquisitions	2,566	8,962
Other	0
Goodwill, ending balance	30,720	28,154
Western
Goodwill [Roll Forward]
Goodwill, beginning balance	120,536	89,369
Acquisitions	23,138	31,167
Other	(2,619)
Goodwill, ending balance	141,055	120,536
Recycling
Goodwill [Roll Forward]
Goodwill, beginning balance	12,315	12,315
Acquisitions	0	0
Other	0
Goodwill, ending balance	12,315	12,315
Other
Goodwill [Roll Forward]
Goodwill, beginning balance	1,729	1,729
Acquisitions	0	0
Other	0
Goodwill, ending balance	$ 1,729	$ 1,729

X

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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-Topic 350
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-Paragraph 1
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- Definition

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.

+ References

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-Publisher FASB
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- Definition

Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-SubTopic 20
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