CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)	Jun. 30, 2015	Apr. 01, 2015	Jun. 30, 2014
GTN \| Transaction between entities under common control \| Former parent, TransCanada subsidiaries
GTN ACQUISITION
Business Acquisition, Percentage of Voting Interests Acquired	30.00%	30.00%	30.00%

Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant