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Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
TOTALEnergies S.E.
Related Party Transaction [Line Items]
Proceeds from related party	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Related Party \| SAFE S.p.A.
Related Party Transaction [Line Items]
Payable to related parties	0.4		0.4		$ 0.3
Related Party \| Management Fee for Services \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Proceeds from related party	0.9	0.8	1.7	1.6
Receivables from related party	1.3		1.3		0.4
Related Party \| Business Expenses Reimbursement \| TOTALEnergies S.E.
Related Party Transaction [Line Items]
Related party expense	0.2	1.6	0.4	3.2
Related Party \| Business Expenses Reimbursement \| SAFE S.p.A.
Related Party Transaction [Line Items]
Related party expense	0.4		0.8	2.5
Related Party \| Business Expenses Reimbursement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Receivables from related party	0.2		0.2		0.4
Related party expense	0.1		0.1	0.1
Related Party \| Management Fee for Services & Business Expenses Reimbursement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Proceeds from related party	1.0	1.0	1.6	1.9
Related Party \| Sharing of Environmental Credits \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Related party expense	0.9	1.2	1.9	2.3
Payable to related parties	0.4		0.4		0.6
Related Party \| Guaranty Agreement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Tax credit loss	38.3		38.3
Fee received			0.7
Other Equity Method Investees \| Rimere
Related Party Transaction [Line Items]
Proceeds from related party	0.0	0.1	0.0	0.1
Receivables from related party	0.0		0.0		0.0
Other Equity Method Investees \| Management Fee for Services \| Rimere
Related Party Transaction [Line Items]
Proceeds from related party	0.2	0.2	0.3	0.3
Receivables from related party	0.1		0.1		0.1
Other Equity Method Investees \| Loan Commitment \| Rimere
Related Party Transaction [Line Items]
Amount provided for funding in certain equity method investee	0.9	$ 0.0	2.4	$ 3.5
Other Equity Method Investees \| Loan Commitment \| Convertible promissory note \| Rimere
Related Party Transaction [Line Items]
Receivables from related party	$ 0.6		$ 0.6		$ 0.3