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Landfill Accounting - Reserve Assumptions and Accretion Expense (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Landfill Accounting [Line Items] |  |  |
Accretion expense associated with landfill obligations | $ 35,793 | $ 22,768 |
Landfill |  |  |
Landfill Accounting [Line Items] |  |  |
Inflation rate for purposes of computing layers for final capping, closure and post-closure obligations | 2.75% |  | 2.75%
Landfill | Measurement input, discount rate |  |  |
Landfill Accounting [Line Items] |  |  |
Discount rate for purposes of computing layers for final capping, closure and post-closure obligations | 5.50% |  | 5.50%

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- Definition 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481879/410-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 + Details
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- Definition The inflation rate applied to the total final capping, closure and post-closure obligation in current dollars based upon the expected date of the expenditure. This inflated total is then discounted to its present value using a credit-adjusted risk free rate. + References No definition available. + Details
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