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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Landfill Development Cost- Additional Information (Detail) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2016 USD ($) Agreement	Dec. 31, 2015 USD ($)	Apr. 30, 2014 USD ($)
Property, Plant and Equipment [Line Items]
Capitalized interest	$ 333	$ 273	$ 62	$ 256
Closure and post-closure costs incurrence period		30 years
Estimate of inflation rate		1.70%
Accretion expense		$ 3,606	3,370
Number of operation and management agreements entered into | Agreement		5
Minimum
Property, Plant and Equipment [Line Items]
Rate of asset retirement obligation		9.20%
Maximum
Property, Plant and Equipment [Line Items]
Rate of asset retirement obligation		9.90%
Closure And Post Closure Costs
Property, Plant and Equipment [Line Items]
Accretion expense	$ 2,275	$ 3,606	3,370	$ 3,967
Surety bond		161,095	156,163
Letters of credit		$ 0	$ 1,000

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Closure and Post-Closure Costs Incurrence Period

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Number of Landfill Operation and Management Agreements Entered Into

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Amount of surety bonds that are available for the future payment of landfill capping, closure and post-closure obligations.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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