Percent of Par

No definition available.

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Namespace Prefix:	mplx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Balance Type:	na
Period Type:	instant

- Definition

Date the debt instrument was issued, in YYYY-MM-DD format.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period Type:	duration

- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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- Details

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Senior Notes (Details) - Senior Notes [Member] - USD ($) $ in Millions	Mar. 02, 2026	Feb. 12, 2026	Mar. 31, 2026	Aug. 11, 2025
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 4,500
Senior Note Due April 20236
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.30%
Debt Instrument, Face Amount		$ 1,000
Debt Instrument, Issuance Date		Feb. 12, 2026
Percent of Par		99.678%
Senior Note Due April 2056
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		6.10%
Debt Instrument, Face Amount		$ 500
Debt Instrument, Issuance Date		Feb. 12, 2026
Percent of Par		98.453%
Senior Notes Due March 2026
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.75%
Repayments of Debt	$ 1,500
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			2.65%
Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.20%