v3.24.3
Senior Notes (Details) - Senior Notes [Member] - USD ($)
$ in Millions
Sep. 30, 2024
May 20, 2024
Senior Note Due June 2034 [Domain]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage   5.50%
Percent of Par   98.778%
Debt Instrument, Face Amount   $ 1,650
Senior Notes Due December 2024 | MPLX LP [Member]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage 4.875%  
Debt Instrument, Face Amount $ 1,149  
Senior Notes Due December 2024 | MarkWest [Member]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage 4.875%  
Debt Instrument, Face Amount $ 1  
Senior Notes Due February 2025 | MPLX LP [Member]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage 4.00%  
Debt Instrument, Face Amount $ 500  
Minimum [Member]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage 1.75%  
Maximum [Member]    
Debt Instrument [Line Items]    
Debt Instrument, Interest Rate, Stated Percentage 5.65%