Inventory - Carrying Value (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Inventory [Line Items]
Feedstocks, raw materials and supplies	$ 304.4	$ 378.0
Refined products and blendstock	464.9	515.2
Total	769.3	893.2
Titled Inventory
Inventory [Line Items]
Feedstocks, raw materials and supplies	194.3	246.5
Refined products and blendstock	267.0	243.4
Total	461.3	489.9
Inventory Intermediation Agreement obligation
Inventory [Line Items]
Feedstocks, raw materials and supplies	110.1	131.5
Refined products and blendstock	197.9	271.8
Total	$ 308.0	$ 403.3

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments.

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