v3.10.0.1

RELATED PARTY TRANSACTIONS (Joint Funding Arrangement Discussions) (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	Apr. 27, 2017	Jan. 26, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Proceeds from related party debt					$ 297	$ 1,500
Income from equity investment in joint venture (Note 7)			$ 37	$ 22	93	28
Acquisition of noncontrolling interest in subsidiary					360
Proceeds from noncontrolling interests					205	1,390
Line 3 Replacement [Member]
Consideration transferred		$ 450			189	185
Joint funding arrangement, parent (in percent)		99.00%
Joint funding arrangement noncontrolling interest (in percentage)		1.00%
Option to increase general partnership interest percentage (in percentage)		40.00%
Acquisition of noncontrolling interest in subsidiary					40
Bakken Pipeline Systems [Member]
Ownership interest in affiliate of Partnership (in percentage)	25.00%
Additional acquisitions percentages	20.00%
Consideration transferred					7	30
Eastern Access Pipeline [Member]
Consideration transferred					$ 1	9
Acquisition of noncontrolling interest in subsidiary		$ 360
Additional acquisition percentages		15.00%
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest		25.00%			40.00%
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		75.00%			60.00%
US Mainline Expansion Interests [Member]
Noncontrolling interest, ownership percentage by parent (in percent)			75.00%		75.00%
Ownership interest in affiliate of Partnership (in percentage)					25.00%
Additional acquisition percentages					15.00%
Proceeds from noncontrolling interests					$ 8	27
General Partner [Member]
Consideration transferred					$ 0	$ 92
Proceeds from related party debt				$ 1,100
Enbridge Holdings DakTex LLC Interests [Member] \| Bakken Pipeline Systems [Member]
Noncontrolling interest, ownership percentage by parent (in percent)	75.00%

The percentage of additional interest acquired by the entity.

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The percentage of additional interest acquired by the entity.

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The percentage of joint funding arrangement non-controlling interest.

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Represents the percentage of parent entity's funding in a joint funding arrangement

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No definition available.

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The percentage of option to increase general partnership interest percentage.

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The percentage of ownership interest in affiliate of Partnership.

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Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

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The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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ENBRIDGE ENERGY PARTNERS LP 10-Q