Debt and Credit Agreements - Schedule of Long-term Debt - New Enviri (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Debt obligation	$ 1,592,425	$ 1,567,001
Less: deferred financing costs	(9,839)	(10,818)
Total debt obligations, net of deferred financing costs	1,582,586	1,556,183
Current maturities of long-term debt	(25,835)	(25,874)
Long-term debt	1,556,751	1,530,309
Other financing payable (including finance leases) in varying amounts
Debt Instrument [Line Items]
Debt obligation	84,175	88,501
Term Loan Facility \| Term Loan
Debt Instrument [Line Items]
Debt obligation	476,250	477,500
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt obligation	557,000	526,000
Senior Notes \| 5.75% Senior Notes
Debt Instrument [Line Items]
Debt obligation	$ 475,000	475,000
Interest rate	5.75%
New Enviri
Debt Instrument [Line Items]
Current maturities of long-term debt	$ (14,011)	(14,373)
New Enviri \| Nonrelated Party
Debt Instrument [Line Items]
Debt obligation	1,532,857	1,505,263
Less: deferred financing costs	(9,839)	(10,818)
Total debt obligations, net of deferred financing costs	1,523,018	1,494,445
Current maturities of long-term debt	(14,011)	(14,373)
Long-term debt	1,509,007	1,480,072
New Enviri \| Other financing payable (including finance leases) in varying amounts \| Nonrelated Party
Debt Instrument [Line Items]
Debt obligation	24,607	26,763
New Enviri \| Term Loan Facility \| Term Loan \| Nonrelated Party
Debt Instrument [Line Items]
Debt obligation	476,250	477,500
New Enviri \| Line of Credit \| Revolving Credit Facility \| Nonrelated Party
Debt Instrument [Line Items]
Debt obligation	557,000	526,000
New Enviri \| Senior Notes \| 5.75% Senior Notes \| Nonrelated Party
Debt Instrument [Line Items]
Debt obligation	$ 475,000	$ 475,000

Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

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