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Goodwill - Additional Information (Details) - USD ($)
3 Months Ended 12 Months Ended
Dec. 31, 2018
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2020
Mar. 01, 2017
Goodwill [Line Items]          
Goodwill $ 46,600,000 $ 45,200,000 $ 46,600,000 $ 45,200,000  
Goodwill impairment $ 210,000,000.0   $ 210,000,000.0    
Other Long-term Assets [Member]          
Goodwill [Line Items]          
Goodwill       $ 45,200,000  
Acquisition of Gas Gathering and Processing and Crude Oil Gathering Assets in Permian Basin [Member]          
Goodwill [Line Items]          
Goodwill         $ 46,600,000
Former Permian Supersystem [Member]          
Goodwill [Line Items]          
Goodwill impairment   $ 0