SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 147,455	$ 133,802
Depreciation and amortization	15,983	13,849
Operating income (loss)	838	6,564
Total assets	631,375	621,249	$ 614,949
Operating Segments \| Eastern
Segment Reporting Information [Line Items]
Revenues	44,505	38,686
Depreciation and amortization	5,979	5,404
Operating income (loss)	(1,812)	21
Total assets	174,860	197,817
Operating Segments \| Western
Segment Reporting Information [Line Items]
Revenues	64,739	54,144
Depreciation and amortization	8,032	6,604
Operating income (loss)	7,194	4,089
Total assets	342,285	324,262
Operating Segments \| Recycling
Segment Reporting Information [Line Items]
Revenues	10,157	16,635
Depreciation and amortization	1,054	1,004
Operating income (loss)	(5,167)	1,583
Total assets	47,065	50,138
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenues	28,054	24,337
Depreciation and amortization	918	837
Operating income (loss)	623	871
Total assets	67,165	49,032
Eliminations
Segment Reporting Information [Line Items]
Revenues	(31,439)	(25,433)
Depreciation and amortization	0	0
Operating income (loss)	0	0
Total assets	0	0
Eliminations \| Eastern
Segment Reporting Information [Line Items]
Revenues	11,306	9,522
Eliminations \| Western
Segment Reporting Information [Line Items]
Revenues	18,631	15,781
Eliminations \| Recycling
Segment Reporting Information [Line Items]
Revenues	1,185	(244)
Eliminations \| Other
Segment Reporting Information [Line Items]
Revenues	$ 317	$ 374

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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