Landfill Accounting - Liability Adjustments and Restricted Cash and Investments (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Landfill Accounting [Line Items]
Liability adjustments	$ 37,482
Final capping, closure and post-closure liability - current portion	161,230	$ 199,735
Final capping, closure and post-closure liability - noncurrent portion	551,706	660,388
Restricted cash	172,989	135,807
Restricted investments	80,002	78,126
Landfill
Landfill Accounting [Line Items]
Restricted cash	9,771	8,852
Restricted investments	$ 79,900	$ 77,855

Current portion of 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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481850/410-20-50-1

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

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-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
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- Definition

Noncurrent portion of 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.

+ References

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- Definition

Amount of cash and cash equivalent restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

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- Definition

This element represents the noncurrent portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477220/954-210-45-4

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-URI https://asc.fasb.org/1943274/2147478600/954-210-50-2

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- Definition

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.

+ References

No definition available.

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