Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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MPLX LP - Public Offerings (Details) - MPLX LP - USD ($) $ in Millions	Mar. 01, 2017	Mar. 31, 2017	Feb. 10, 2017	Dec. 31, 2016
Senior Notes \| MPLX senior notes, 4.125%, due March 2027
Noncontrolling Interest [Line Items]
Long-term debt, gross		$ 1,250	$ 1,250	$ 0
Debt instrument, interest rate		4.125%	4.125%
Senior Notes \| MPLX senior notes, 5.200%, due March 2047
Noncontrolling Interest [Line Items]
Long-term debt, gross		$ 1,000	$ 1,000	$ 0
Debt instrument, interest rate		5.20%	5.20%
Cash and Cash Equivalents
Noncontrolling Interest [Line Items]
Payments to acquire business, gross	$ 1,500