SIGNIFICANT ACCOUNTING POLICIES (Details) (Former parent, TransCanada subsidiaries, Transaction between entities under common control)	Jul. 02, 2013	May 03, 2011
GTN
Summary of Significant Accounting Policies
Interest acquired by the Partnership (as a percent)	45.00%	25.00%
Bison
Summary of Significant Accounting Policies
Interest acquired by the Partnership (as a percent)	45.00%	25.00%

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=25497992&loc=d3e1392-128463

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