SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 154,016	$ 144,670	$ 287,818	$ 270,103
Depreciation and amortization	15,868	15,802	29,717	30,255
Operating income (loss)	(47,279)	15,596	(40,714)	17,570
Total assets	588,877	631,621	588,877	631,621	$ 631,512
Operating Segments
Segment Reporting Information [Line Items]
Revenues			287,818	270,103
Operating Segments \| Eastern
Segment Reporting Information [Line Items]
Revenues	46,574	45,405	85,260	84,392
Depreciation and amortization	6,423	7,138	11,827	13,327
Operating income (loss)	(60,324)	3,079	(60,304)	2,291
Total assets	158,042	208,316	158,042	208,316
Operating Segments \| Western
Segment Reporting Information [Line Items]
Revenues	64,372	59,460	118,515	111,922
Depreciation and amortization	7,586	6,908	14,191	13,398
Operating income (loss)	10,770	10,175	14,859	13,169
Total assets	328,207	319,480	328,207	319,480
Operating Segments \| Recycling
Segment Reporting Information [Line Items]
Revenues	16,211	12,816	32,846	23,454
Depreciation and amortization	1,019	1,040	2,022	2,132
Operating income (loss)	1,064	468	2,647	(606)
Total assets	50,398	48,782	50,398	48,782
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenues	26,859	26,989	51,197	50,335
Depreciation and amortization	840	716	1,677	1,398
Operating income (loss)	1,211	1,874	2,084	2,716
Total assets	52,230	55,043	52,230	55,043
Inter-company revenue \| Eastern
Segment Reporting Information [Line Items]
Revenues	13,202	11,692	22,724	21,229
Inter-company revenue \| Western
Segment Reporting Information [Line Items]
Revenues	18,625	17,889	34,407	32,740
Inter-company revenue \| Recycling
Segment Reporting Information [Line Items]
Revenues	(245)	302	(489)	933
Inter-company revenue \| Other
Segment Reporting Information [Line Items]
Revenues	611	404	985	684
Eliminations
Segment Reporting Information [Line Items]
Revenues	(32,193)	(30,287)	(57,627)	(55,586)
Depreciation and amortization	0	0	0	0
Operating income (loss)	0	0	0	0
Total assets	$ 0	$ 0	$ 0	$ 0

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))
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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=66902209&loc=d3e3602-108585

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-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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