EQT Midstream Partners, LP (Details) - EQM - Subsequent Event - USD ($) $ / shares in Units, $ in Millions	Apr. 26, 2018	Apr. 24, 2018
Subsidiary or equity method investee
Distribution made to limited partner and general partner, cash distributions declared	$ 69.7
Cash distribution declared	23.2
Distribution made to general partner, cash distributions declared	2.3
Cash distribution declared related to IDRs	$ 44.2
General Partner
Subsidiary or equity method investee
Cash distribution declared (in dollars per share)		$ 1.065
Common unit, outstanding (in shares)	80,591,366

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

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