Debt (Outstanding Borrowings) (Detail) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Total debt	$ 29,281	$ 27,620
Unamortized debt issuance costs	(149)	(141)
Unamortized discount, net of unamortized premium	(195)	(196)
Amounts due within one year	(4,903)	(1,954)
Long-term debt	24,034	25,329
Marathon Petroleum Corporation:
Finance lease obligations	475	464
Total debt	6,925	6,914
Marathon Petroleum Corporation: \| Senior notes
Long-term debt, gross	6,449	6,449
Marathon Petroleum Corporation: \| Notes payable
Long-term debt, gross	1	1
MPLX LP:
Finance lease obligations	6	6
Total debt	22,356	20,706
MPLX LP: \| Senior notes
Long-term debt, gross	$ 22,350	$ 20,700

Amount of short-term and long-term debt and lease obligation.

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