DEBT - Schedule of Long-term Debt Issuances (Details) - CAD CAD in Millions	1 Months Ended
	Oct. 31, 2017	Sep. 30, 2017	Jul. 31, 2017	Jun. 30, 2017	May 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Nov. 30, 2017	Jul. 13, 2017	Nov. 30, 2016	Aug. 31, 2016
Enbridge Gas Distribution Inc. | 3.51% medium-term notes due November 2047
Debt Instrument [Line Items]
Principal Amount								CAD 300
Fixed interest rate (as a percent)							3.51%
Enbridge Gas Distribution Inc. | 2.50% medium-term notes due August 2026
Debt Instrument [Line Items]
Principal Amount											CAD 300
Fixed interest rate (as a percent)							2.50%
Enbridge Pipelines Inc. | 3.00% medium-term notes due August 2026
Debt Instrument [Line Items]
Principal Amount											400
Fixed interest rate (as a percent)							3.00%
Enbridge Pipelines Inc. | 4.13% medium-term notes due August 2046
Debt Instrument [Line Items]
Principal Amount											CAD 400
Fixed interest rate (as a percent)							4.13%
Spectra Energy Partners, LP | Floating rate notes due June 2020
Debt Instrument [Line Items]
Principal Amount				CAD 400
Basis spread on variable rate (as a percent)				0.70%
Union Gas Limited | 2.88% medium-term notes due November 2027
Debt Instrument [Line Items]
Principal Amount								250
Fixed interest rate (as a percent)							2.88%
Union Gas Limited | 3.59% medium-term notes due November 2047
Debt Instrument [Line Items]
Principal Amount								CAD 250
Fixed interest rate (as a percent)							3.59%
Enbridge Inc. | Floating rate notes due May 2019
Debt Instrument [Line Items]
Principal Amount					CAD 750
Basis spread on variable rate (as a percent)					0.59%
Enbridge Inc. | 3.19% medium-term notes due December 2022
Debt Instrument [Line Items]
Principal Amount				CAD 450
Fixed interest rate (as a percent)							3.19%
Enbridge Inc. | 3.20% medium-term notes due June 2027
Debt Instrument [Line Items]
Principal Amount				450
Fixed interest rate (as a percent)							3.20%
Enbridge Inc. | 4.57% medium-term notes due March 2044
Debt Instrument [Line Items]
Principal Amount				300
Fixed interest rate (as a percent)							4.57%
Enbridge Inc. | Floating rate notes due June 2020
Debt Instrument [Line Items]
Principal Amount				CAD 500
Basis spread on variable rate (as a percent)				0.70%
Enbridge Inc. | 2.90% senior notes due July 2022
Debt Instrument [Line Items]
Principal Amount			CAD 700
Fixed interest rate (as a percent)							2.90%
Enbridge Inc. | 3.70% senior notes due July 2027
Debt Instrument [Line Items]
Principal Amount			700
Fixed interest rate (as a percent)							3.70%
Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Principal Amount			CAD 1,000
Term of credit facility			60 years
Callable period			10 years
Term of fixed rate			10 years
Fixed interest rate (as a percent)			5.50%
Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Principal Amount	CAD 650	CAD 1,000
Term of credit facility		60 years
Callable period		10 years
Term of fixed rate		10 years
Fixed interest rate (as a percent)		5.40%
Enbridge Inc. | Floating rate notes due January 2020
Debt Instrument [Line Items]
Principal Amount	CAD 700
Basis spread on variable rate (as a percent)	0.40%
Enbridge Inc. | 4.25% medium-term notes due December 2026
Debt Instrument [Line Items]
Principal Amount										CAD 750
Fixed interest rate (as a percent)							4.25%
Enbridge Inc. | 5.50% medium-term notes due December 2046
Debt Instrument [Line Items]
Principal Amount										CAD 750
Fixed interest rate (as a percent)							5.50%
Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Principal Amount						CAD 750
Term of credit facility						60 years
Callable period						10 years
Term of fixed rate						10 years
Fixed interest rate (as a percent)						6.00%
Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate			10 years
Maximum
Debt Instrument [Line Items]
Fixed interest rate (as a percent)							7.50%		7.50%
Debt Instrument, Redemption, Period One | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			3.42%
Debt Instrument, Redemption, Period One | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		3.25%
Debt Instrument, Redemption, Period One | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						3.89%
Debt Instrument, Redemption, Period One | Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate		10 years
Debt Instrument, Redemption, Period One | Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate						10 years
Debt Instrument, Redemption, Period One | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate			30 years
Debt Instrument, Redemption, Period One | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate		30 years
Debt Instrument, Redemption, Period One | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate						30 years
Debt Instrument, Redemption, Period Two | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)			4.17%
Debt Instrument, Redemption, Period Two | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		4.00%
Debt Instrument, Redemption, Period Two | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)						4.64%
Debt Instrument, Redemption, Period Two | Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate			30 years
Debt Instrument, Redemption, Period Two | Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate		30 years
Debt Instrument, Redemption, Period Two | Minimum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate						30 years
Debt Instrument, Redemption, Period Two | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due July 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate			60 years
Debt Instrument, Redemption, Period Two | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due September 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate		60 years
Debt Instrument, Redemption, Period Two | Maximum | Enbridge Inc. | Fixed-to-floating rate subordinated notes due January 2077
Debt Instrument [Line Items]
Period when the notes carry a variable interest rate						60 years