Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

No definition available.

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Data Type:	xbrli:integerItemType
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Period Type:	duration

Overview - Additional Information (Detail) barrel / d in Thousands	12 Months Ended
	Dec. 31, 2019 barrel / d segment gasoline_store_facility refinery	Oct. 18, 2018	Feb. 28, 2018	Mar. 01, 2016
Operating segments \| segment	3
Number of owned and operated refineries \| refinery	4
Oil and gas refinery \| barrel / d	200
Number of retail outlets	124
Number of fueling stations, rebranded	40
Convenience stores, rebranded	28
Convenience store facilities	34
Laramie Energy Company
Ownership of Laramie Energy, LLC	46.00%	46.00%	39.10%	42.30%