EQT Midstream Partners, LP (Details) - EQM - Subsequent Event - USD ($) $ / shares in Units, $ in Millions	Oct. 26, 2017	Oct. 24, 2017
Subsidiary or equity method investee
Distribution made to limited partner and general partner, cash distributions declared	$ 61.1
Cash distribution declared	21.4
Distribution made to general partner, cash distributions declared	2.1
Cash distribution declared related to IDRs	$ 37.6
General Partner
Subsidiary or equity method investee
Cash distribution declared (in dollars per share)		$ 0.98
Common unit, outstanding (in shares)	80,581,758

Distribution Made to General Partner, Cash Distributions Declared

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Distribution Made to Limited Partner and General Partner, Cash Distributions Declared

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Incentive Distribution, Distribution Declared

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Number of common units of ownership outstanding of a limited liability company (LLC).

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Amount of equity impact of cash distribution declared to unit-holder of limited partnership (LP).

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Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

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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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