v3.26.1
Components of Accumulated Other Comprehensive Loss - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance $ 274,911 $ 295,587 $ 432,533 $ 429,666 $ 295,587 $ 429,666
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax         11,976 7,592
Amounts reclassified from AOCI, net of tax         7,770 9,482
Total other comprehensive income (loss) 14,958 4,788 8,960 8,114 19,746 17,074
Less: OCI attributable to noncontrolling interests         (532) (1,155)
Ending balance 682,687 274,911 400,398 432,533 682,687 400,398
Cumulative Foreign Exchange Translation Adjustments            
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance   (199,071)   (229,257) (199,071) (229,257)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax         3,783 36,903
Amounts reclassified from AOCI, net of tax         0 0
Total other comprehensive income (loss)         3,783 36,903
Less: OCI attributable to noncontrolling interests         (532) (1,155)
OCI attributable to Enviri Corporation         3,251 35,748
Ending balance (195,820)   (193,509)   (195,820) (193,509)
Effective Portion of Derivatives Designated as Hedging Instruments            
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance   15   3,769 15 3,769
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax         4,234 (5,019)
Amounts reclassified from AOCI, net of tax         (1,520) 422
Total other comprehensive income (loss)         2,714 (4,597)
Less: OCI attributable to noncontrolling interests         0 0
OCI attributable to Enviri Corporation         2,714 (4,597)
Ending balance 2,729   (828)   2,729 (828)
Cumulative Unrecognized Actuarial Losses on Pension Obligations            
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance   (315,450)   (311,919) (315,450) (311,919)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax         3,939 (24,298)
Amounts reclassified from AOCI, net of tax         9,290 9,060
Total other comprehensive income (loss)         13,229 (15,238)
Less: OCI attributable to noncontrolling interests         0 0
OCI attributable to Enviri Corporation         13,229 (15,238)
Ending balance (302,221)   (327,157)   (302,221) (327,157)
Unrealized Gain (Loss) on Marketable Securities            
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance   25   22 25 22
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax         20 6
Amounts reclassified from AOCI, net of tax         0 0
Total other comprehensive income (loss)         20 6
Less: OCI attributable to noncontrolling interests         0 0
OCI attributable to Enviri Corporation         20 6
Ending balance 45   28   45 28
Accumulated Other Comprehensive Loss            
Components of Accumulated Other Comprehensive Income [Roll Forward]            
Beginning balance (509,773) (514,481) (529,638) (537,385) (514,481) (537,385)
Total other comprehensive income (loss) 14,506 4,708 8,172 7,747    
OCI attributable to Enviri Corporation         19,214 15,919
Ending balance $ (495,267) $ (509,773) $ (521,466) $ (529,638) $ (495,267) $ (521,466)