Number of related party capital lease agreements entered into.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of cash paid during the period to settle an asset retirement obligation. Amounts paid to settle an asset retirement obligation are generally included in the operating section of the Statement of Cash Flows.

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The charge for the use of long-lived depreciable capital leased assets for the period.

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Amount of the required periodic payments including both interest and principal payments.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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RELATED PARTY TRANSACTIONS (Detail) $ in Thousands	12 Months Ended
RELATED PARTY TRANSACTIONS (Detail) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 30, 1994 lease
Related Party Transaction [Line Items]
Total services purchased	$ 13,046	$ 7,574	$ 3,442
Outstanding accounts payable	1,297	851
Number of leases \| lease				2
Amortization of right-of-use assets	3,736	2,122
Accrued costs associated with post-closure obligations	82,533	71,927	73,075
Landfills
Related Party Transaction [Line Items]
Landfill post-closure cost	8	9	14
Accrued costs associated with post-closure obligations	25	37
CCI
Related Party Transaction [Line Items]
Revenue from related party	288	132	156
Related Party
Related Party Transaction [Line Items]
Leases monthly payments	29
Amortization of right-of-use assets	$ 319	$ 339
Total expense charged to operations under lease agreement			$ 349