Revenue - product sales and recycling services - Movement In Deferred Revenue (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Movement in Deferred Revenue [Roll Forward]
Current deferred revenue	$ 0.0	$ 0.2
Non-current deferred revenue	5.8	5.3
Product revenue
Movement in Deferred Revenue [Roll Forward]
Balance, beginning of the period	0.0	0.0
Additions	7.8	0.0
Revenue recognized	(7.8)	0.0
Balance, end of the period	0.0	0.0
Current deferred revenue	0.0	0.0
Non-current deferred revenue	0.0	0.0
Service
Movement in Deferred Revenue [Roll Forward]
Balance, beginning of the period	5.5	0.0
Additions	0.0	5.4
Foreign exchange revaluation	0.3	0.1
Balance, end of the period	5.8	5.5
Current deferred revenue	0.0	0.2
Non-current deferred revenue	$ 5.8	$ 5.3