Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party \| TOTALEnergies S.E.
Related Party Transaction [Line Items]
Proceeds from related party	$ 0.0	$ 1.4	$ 7.6
Related Party \| SAFE S.p.A.
Related Party Transaction [Line Items]
Proceeds from related party	0.1	0.3	0.2
Receivables from related party		0.3
Payable to related parties	0.3	8.1
Related Party \| Management Fee for Services \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Proceeds from related party	3.1	3.1	1.3
Receivables from related party	0.4	0.3
Related Party \| Business Expenses Reimbursement \| TOTALEnergies S.E.
Related Party Transaction [Line Items]
Related party expense	3.6	6.9	8.4
Related Party \| Business Expenses Reimbursement \| SAFE S.p.A.
Related Party Transaction [Line Items]
Related party expense	6.0	12.6	16.7
Related Party \| Business Expenses Reimbursement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Receivables from related party	0.4	0.7
Related party expense	0.0	1.2	0.6
Related Party \| Management Fee for Services & Business Expenses Reimbursement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Proceeds from related party	4.1	5.0	1.5
Related party expense		0.0	0.0
Related Party \| Sharing of Environmental Credits \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Related party expense	4.5
Payable to related parties	0.6	0.6	$ 0.0
Other Equity Method Investees \| Rimere
Related Party Transaction [Line Items]
Proceeds from related party		0.0
Receivables from related party	0.0	0.0
Other Equity Method Investees \| Management Fee for Services \| Rimere
Related Party Transaction [Line Items]
Proceeds from related party	0.6	0.6
Receivables from related party	0.1	0.7
Other Equity Method Investees \| Loan Commitment \| Rimere
Related Party Transaction [Line Items]
Amount provided for funding in certain equity method investee	6.0	3.5
Other Equity Method Investees \| Loan Commitment \| Convertible promissory note \| Rimere
Related Party Transaction [Line Items]
Receivables from related party	0.3	$ 2.3
Other Equity Method Investees \| Equipment Sold \| Rimere
Related Party Transaction [Line Items]
Proceeds from related party	$ 0.1

The amount of repayments of loan with equity method investee.

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