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Segment Information - Narrative (Details)
12 Months Ended
Dec. 31, 2020
segment
Segment Reporting Information [Line Items]  
Number of reportable segments 3
UNEV Pipeline  
Segment Reporting Information [Line Items]  
Equity method investment, ownership percentage 75.00%
Osage Pipeline  
Segment Reporting Information [Line Items]  
Equity method investment, ownership percentage 50.00%