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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Landfill and Lease Accounting (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Agreement	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Capitalized interest	$ 263	$ 140	$ 295
Closure and post-closure costs incurrence period	30 years
Estimate of inflation rate	1.60%
Accretion expense	$ 6,227	5,556
Number of operation and management agreements entered into | Agreement	3
Closure And Post Closure Costs
Property, Plant and Equipment [Line Items]
Accretion expense	$ 6,227	5,556	$ 4,401
Surety bond	220,633	201,177
Letters of credit	$ 0	$ 0
Discount rate | Minimum
Property, Plant and Equipment [Line Items]
Asset retirement obligation measurement input	8.70%
Discount rate | Maximum
Property, Plant and Equipment [Line Items]
Asset retirement obligation measurement input	10.00%

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Number of Landfill Operation and Management Agreements Entered Into

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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