CONTINGENCIES (Details) $ in Millions	Apr. 01, 2015 USD ($)
Former parent, TransCanada subsidiaries \| Transaction between entities under common control \| GTN \| Partnership interest \| Class B units
Contingencies
Equity issuance	$ 95

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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