SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 187,459	$ 165,649	$ 351,123	$ 313,104
Depreciation and amortization	19,715	17,386	37,204	33,370
Operating income (loss)	15,544	15,149	19,986	15,986
Total assets	865,960		865,960		$ 732,410
Operating Segments
Segment Reporting Information [Line Items]
Revenues	187,459	165,649	351,123	313,104
Depreciation and amortization	19,715	17,386	37,204	33,370
Operating income (loss)	15,544	15,149	19,986	15,986
Total assets	865,960	652,574	865,960	652,574
Operating Segments \| Eastern
Segment Reporting Information [Line Items]
Revenues	57,076	53,589	104,073	98,094
Depreciation and amortization	6,368	7,030	11,629	13,009
Operating income (loss)	4,227	4,266	3,600	2,454
Total assets	211,891	180,330	211,891	180,330
Operating Segments \| Western
Segment Reporting Information [Line Items]
Revenues	85,356	71,043	158,989	135,783
Depreciation and amortization	11,419	8,351	21,659	16,382
Operating income (loss)	10,338	11,989	15,696	19,182
Total assets	530,756	354,284	530,756	354,284
Operating Segments \| Recycling
Segment Reporting Information [Line Items]
Revenues	10,514	9,600	21,280	19,757
Depreciation and amortization	978	1,043	1,947	2,097
Operating income (loss)	(214)	(2,250)	(1,155)	(7,418)
Total assets	54,964	49,477	54,964	49,477
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenues	34,513	31,417	66,781	59,470
Depreciation and amortization	950	962	1,969	1,882
Operating income (loss)	1,193	1,144	1,845	1,768
Total assets	68,349	68,483	68,349	68,483
Eliminations
Segment Reporting Information [Line Items]
Revenues	(41,914)	(37,598)	(75,290)	(69,038)
Eliminations \| Eastern
Segment Reporting Information [Line Items]
Revenues	14,678	14,569	25,449	25,876
Eliminations \| Western
Segment Reporting Information [Line Items]
Revenues	24,213	20,689	44,314	39,320
Eliminations \| Recycling
Segment Reporting Information [Line Items]
Revenues	2,363	1,738	4,334	2,923
Eliminations \| Other
Segment Reporting Information [Line Items]
Revenues	$ 660	$ 602	$ 1,193	$ 919

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.

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