Major Customers	12 Months Ended
Dec. 31, 2020
Segment Reporting [Abstract]
Major Customers	Major CustomersSales to Valero Energy Corporation constituted approximately 17%, 12% and 10% of total revenues (before the effects of hedging) for the years ended December 31, 2020, 2019 and 2018, respectively. No other purchasers accounted for more than 10% of our total revenues in 2020, 2019 or 2018.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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