Debt - Outstanding Borrowings (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Total debt	$ 28,855	$ 27,980
Unamortized debt issuance costs	(124)	(128)
Unamortized discount	(324)	(328)
Amounts due within one year	(554)	(544)
Total long-term debt due after one year	27,853	26,980
Marathon Petroleum Corporation
Total debt	9,119	9,114
MPLX LP
Total debt	14,473	13,856
ANDX LP
Total debt	$ 5,263	$ 5,010

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

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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