SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 182,910	$ 163,664
Depreciation and amortization	21,406	17,489
Operating Income (Loss)	7,012	4,442
Total assets	957,640		$ 932,182
Operating
Segment Reporting Information [Line Items]
Revenues	182,910	163,664
Depreciation and amortization	21,406	17,489
Operating Income (Loss)	7,012	4,442
Total assets	957,640	828,313
Operating \| Eastern
Segment Reporting Information [Line Items]
Revenues	50,143	46,997
Depreciation and amortization	5,958	5,260
Operating Income (Loss)	975	(626)
Total assets	206,334	195,851
Operating \| Western
Segment Reporting Information [Line Items]
Revenues	85,206	74,151
Depreciation and amortization	13,232	10,234
Operating Income (Loss)	5,642	5,378
Total assets	599,815	494,066
Operating \| Resource Solutions
Segment Reporting Information [Line Items]
Revenues	47,561	42,516
Depreciation and amortization	1,610	1,294
Operating Income (Loss)	1,003	401
Total assets	93,199	86,222
Operating \| Corporate entities
Segment Reporting Information [Line Items]
Revenues	0	0
Depreciation and amortization	606	701
Operating Income (Loss)	(608)	(711)
Total assets	58,292	52,174
Inter-company revenues
Segment Reporting Information [Line Items]
Revenues	(40,279)	(33,376)
Inter-company revenues \| Eastern
Segment Reporting Information [Line Items]
Revenues	11,839	10,771
Inter-company revenues \| Western
Segment Reporting Information [Line Items]
Revenues	25,546	20,218
Inter-company revenues \| Resource Solutions
Segment Reporting Information [Line Items]
Revenues	2,894	2,387
Inter-company revenues \| Corporate entities
Segment Reporting Information [Line Items]
Revenues	$ 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.

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