Unaudited condensed consolidated interim statements of equity - USD ($) shares in Millions, $ in Millions	Total	Equity attributable to the shareholders of Li-Cycle Holdings Corp.	Number of common shares	Common stock and additional paid-in capital	Accumulated deficit	Accumulated other comprehensive loss	Non-controlling interest
Beginning balance, common shares, outstanding (in shares) at Dec. 31, 2022			22.0
Beginning balance, equity at Dec. 31, 2022	$ 501.6	$ 501.4		$ 635.3	$ (133.6)	$ (0.3)	$ 0.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Settlement of RSUs (in shares)			0.1
Settlement of RSUs	0.0
Exercise of stock options (in shares)			0.1
Exercise of stock options	0.0
Stock-based compensation - RSUs	5.5	5.5		5.5
Stock-based compensation - options	1.8	1.8		1.8
Payment to the holders of non-controlling interest in subsidiary	(0.6)	(0.4)		(0.4)			(0.2)
Net (loss) income	(68.4)	(68.4)			(68.4)
Comprehensive (loss) income	(68.4)	(68.4)			(68.4)
Ending balance, common shares, outstanding (in shares) at Jun. 30, 2023			22.2
Ending balance, equity at Jun. 30, 2023	439.9	439.9		642.2	(202.0)	(0.3)	0.0
Beginning balance, common shares, outstanding (in shares) at Mar. 31, 2023			22.1
Beginning balance, equity at Mar. 31, 2023	468.5	468.3		638.7	(170.1)	(0.3)	0.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			0.1
Exercise of stock options	0.0
Stock-based compensation - RSUs	2.8	2.8		2.8
Stock-based compensation - options	1.1	1.1		1.1
Payment to the holders of non-controlling interest in subsidiary	(0.6)	(0.4)		(0.4)			(0.2)
Net (loss) income	(31.9)	(31.9)			(31.9)
Comprehensive (loss) income	(31.9)	(31.9)			(31.9)
Ending balance, common shares, outstanding (in shares) at Jun. 30, 2023			22.2
Ending balance, equity at Jun. 30, 2023	$ 439.9	439.9		642.2	(202.0)	(0.3)	0.0
Beginning balance, common shares, outstanding (in shares) at Dec. 31, 2023	22.2		22.2
Beginning balance, equity at Dec. 31, 2023	$ 376.4	376.4		648.3	(271.6)	(0.3)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Settlement of RSUs (in shares)			0.3
Settlement of RSUs	0.0
Stock-based compensation - RSUs	3.2	3.2		3.2
Stock-based compensation - options	1.0	1.0		1.0
Net (loss) income	(144.9)	(144.9)			(144.9)
Comprehensive (loss) income	$ (144.9)	(144.9)			(144.9)
Ending balance, common shares, outstanding (in shares) at Jun. 30, 2024	22.5		22.5
Ending balance, equity at Jun. 30, 2024	$ 235.7	235.7		652.5	(416.5)	(0.3)	0.0
Beginning balance, common shares, outstanding (in shares) at Mar. 31, 2024			22.4
Beginning balance, equity at Mar. 31, 2024	243.0	243.0		651.6	(408.3)	(0.3)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Settlement of RSUs (in shares)			0.1
Settlement of RSUs	0.0
Stock-based compensation - RSUs	0.5	0.5		0.5
Stock-based compensation - options	0.4	0.4		0.4
Net (loss) income	(8.2)	(8.2)			(8.2)
Comprehensive (loss) income	$ (8.2)	(8.2)			(8.2)
Ending balance, common shares, outstanding (in shares) at Jun. 30, 2024	22.5		22.5
Ending balance, equity at Jun. 30, 2024	$ 235.7	$ 235.7		$ 652.5	$ (416.5)	$ (0.3)	$ 0.0