Reconciliation of Basic and Diluted Shares - Reconciliation of Basic and Diluted Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Income (loss) from continuing operations attributable to Enviri Corporation common stockholders	$ (11,995)	$ (9,663)	$ (41,556)	$ (28,539)
Weighted-average shares outstanding - basic (in shares)	80,165	79,850	80,085	79,767
Dilutive effect of stock-based compensation (in shares)	0	0	0	0
Weighted-average shares outstanding - diluted (in shares)	80,165	79,850	80,085	79,767
Earnings (loss) from continuing operations per common share, attributable to Enviri Corporation common stockholders:
Basic (in dollars per share)	$ (0.15)	$ (0.12)	$ (0.52)	$ (0.36)
Diluted (in dollars per share)	$ (0.15)	$ (0.12)	$ (0.52)	$ (0.36)