Debt (Outstanding Borrowings) (Detail) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Total debt	$ 33,272	$ 33,305
Unamortized debt issuance costs	(214)	(204)
Unamortized discount, net of unamortized premium	(233)	(225)
Amounts due within one year	(2,119)	(2,371)
Long-term debt	30,706	30,505
MPC:
Finance lease obligations	663	689
Total debt	7,266	7,299
MPC: \| Senior notes
Long-term debt, gross	6,449	6,449
MPC: \| Bonds
Other long-term debt	154	161
MPLX:
Finance lease obligations	6	6
Total debt	26,006	26,006
MPLX: \| Senior notes
Long-term debt, gross	$ 26,000	$ 26,000

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

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