Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
TOTAL S.A
Related Party Transaction [Line Items]
Proceeds for related party	$ 2.0	$ 1.2	$ 2.6	$ 1.7
Receivables from related party	0.8		0.8		$ 0.0
Related party expense	0.2	0.0	0.4	0.0
SAFE&CEC S.r.l.
Related Party Transaction [Line Items]
Proceeds for related party	0.9	0.2	1.0	0.2
Receivables from related party	0.2		0.2		0.9
Related party expense	1.6	$ 0.5	2.8	$ 1.5
Payable to related parties	$ 0.8		$ 0.8		$ 0.8

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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