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The Equitrans Share Exchange (Details) - Equitrans Midstream
10 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]    
Ownership percentage   19.90%
Subsequent Event | Scenario, Forecast    
Schedule of Equity Method Investments [Line Items]    
Percent of interest sold 50.00%  
Percentage of ownership after transaction 9.95%