EQT Midstream Partners, LP (Details) - EQM - Subsequent Event - USD ($) $ / shares in Units, $ in Millions	Apr. 27, 2017	Apr. 25, 2017
Subsidiary or equity method investee
Cash distribution declared	$ 51.9
General Partner
Subsidiary or equity method investee
Cash distribution declared (in dollars per share)		$ 0.89
Common unit, outstanding (in shares)	80,581,758
Cash distribution declared	$ 1.8
Cash distribution declared related to IDRs	30.7
Limited Partner
Subsidiary or equity method investee
Cash distribution declared	$ 19.4

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Period Type:	duration