CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - CAD CAD in Millions	Total	Preference shares	Common shares	Additional paid-in capital	Retained earnings/(deficit)	Accumulated other comprehensive income/(loss)	Reciprocal shareholding	Total Enbridge Inc. shareholders' equity	Noncontrolling Interest
Balance at Dec. 31, 2014		CAD 6,515	CAD 6,669	CAD 2,549	CAD 1,571	CAD (435)	CAD (83)		CAD 2,015
Increase (Decrease) in Stockholders' Equity
Shares issued		0	0
Common shares issued in Merger Transaction (Note 7)			0
Dividend Reinvestment and Share Purchase Plan			646
Stock-based compensation				35
Fair value of outstanding earned stock-based compensation from Merger Transaction (Note 7)				0
Exercised of stock options			76	(19)
Enbridge Energy Company, Inc. common control transaction				0					0
Drop down of interest to Enbridge Energy Partners, L.P.				218					(304)
Dilution gain/(loss) and other (Note 19)				518
Earnings attributable to controlling interests	CAD 251				251
Preference share dividends					(288)
Common share dividends declared					(1,596)
Dividends paid to reciprocal shareholder					22
Reversal of cumulative redemption value adjustment attributable to Enbridge Commercial Trust (Note 19)					541
Redemption value adjustment attributable to redeemable noncontrolling interests (Note 19)	359				(359)
Adjustment for the recognition of unutilized tax deductions for stock based compensation expense					0
Adjustment relating to equity method investment					0
Other					0
Other comprehensive income/(loss) attributable to common shareholders, net of tax						2,067
Issuance of treasury stock							0
Earnings/(loss) attributable to noncontrolling interests									(407)
Change in unrealized gain on cash flow hedges									161
Foreign currency translation adjustments									273
Reclassification to earnings of (gain)/loss on cash flow hedges									(319)
Other comprehensive income/(loss) attributable to noncontrolling interests, net of tax									115
Comprehensive income/(loss) attributable to noncontrolling interests									(292)
Noncontrolling interests resulting from Merger Transaction (Note 7)									0
Distributions									(680)
Contributions									615
Deconsolidation of Sabal Trail Transmission, LLC									0
Dilution gain/(loss)									(53)
Disposition of Olympic Pipeline									0
Other									(1)
Balance at Dec. 31, 2015	CAD 20,198	6,515	7,391	3,301	142	1,632	(83)	CAD 18,898	1,300
Increase (Decrease) in Stockholders' Equity
Dividends paid per common share	CAD 1.86
Shares issued		740	2,241
Common shares issued in Merger Transaction (Note 7)			0
Dividend Reinvestment and Share Purchase Plan			795
Stock-based compensation				41
Fair value of outstanding earned stock-based compensation from Merger Transaction (Note 7)				0
Exercised of stock options			65	(24)
Enbridge Energy Company, Inc. common control transaction				0					0
Drop down of interest to Enbridge Energy Partners, L.P.				0					0
Dilution gain/(loss) and other (Note 19)				81
Earnings attributable to controlling interests	CAD 2,069				2,069
Preference share dividends					(293)
Common share dividends declared					(1,945)
Dividends paid to reciprocal shareholder					26
Reversal of cumulative redemption value adjustment attributable to Enbridge Commercial Trust (Note 19)					0
Redemption value adjustment attributable to redeemable noncontrolling interests (Note 19)	686				(686)
Adjustment for the recognition of unutilized tax deductions for stock based compensation expense					0
Adjustment relating to equity method investment					(29)
Other					0
Other comprehensive income/(loss) attributable to common shareholders, net of tax						(574)
Issuance of treasury stock							(19)
Earnings/(loss) attributable to noncontrolling interests									(28)
Change in unrealized gain on cash flow hedges									4
Foreign currency translation adjustments									(44)
Reclassification to earnings of (gain)/loss on cash flow hedges									40
Other comprehensive income/(loss) attributable to noncontrolling interests, net of tax									0
Comprehensive income/(loss) attributable to noncontrolling interests									(28)
Noncontrolling interests resulting from Merger Transaction (Note 7)									0
Distributions									(720)
Contributions									28
Deconsolidation of Sabal Trail Transmission, LLC									0
Dilution gain/(loss)									0
Disposition of Olympic Pipeline									0
Other									(3)
Balance at Dec. 31, 2016	CAD 21,963	7,255	10,492	3,399	(716)	1,058	(102)	21,386	577
Increase (Decrease) in Stockholders' Equity
Dividends paid per common share	CAD 2.12
Shares issued		492	1,500
Common shares issued in Merger Transaction (Note 7)			37,429
Dividend Reinvestment and Share Purchase Plan			1,226
Stock-based compensation				82
Fair value of outstanding earned stock-based compensation from Merger Transaction (Note 7)				77
Exercised of stock options			90	(95)
Enbridge Energy Company, Inc. common control transaction				76					(343)
Drop down of interest to Enbridge Energy Partners, L.P.				0					0
Dilution gain/(loss) and other (Note 19)				(345)
Earnings attributable to controlling interests	CAD 2,859				2,859
Preference share dividends					(330)
Common share dividends declared					(4,702)
Dividends paid to reciprocal shareholder					30
Reversal of cumulative redemption value adjustment attributable to Enbridge Commercial Trust (Note 19)					0
Redemption value adjustment attributable to redeemable noncontrolling interests (Note 19)	(292)				292
Adjustment for the recognition of unutilized tax deductions for stock based compensation expense					41
Adjustment relating to equity method investment					0
Other					58
Other comprehensive income/(loss) attributable to common shareholders, net of tax						(2,031)
Issuance of treasury stock							0
Earnings/(loss) attributable to noncontrolling interests									232
Change in unrealized gain on cash flow hedges									15
Foreign currency translation adjustments									(431)
Reclassification to earnings of (gain)/loss on cash flow hedges									139
Other comprehensive income/(loss) attributable to noncontrolling interests, net of tax									(277)
Comprehensive income/(loss) attributable to noncontrolling interests									(45)
Noncontrolling interests resulting from Merger Transaction (Note 7)									8,955
Distributions									(839)
Contributions									832
Deconsolidation of Sabal Trail Transmission, LLC									(2,318)
Dilution gain/(loss)									832
Disposition of Olympic Pipeline									(24)
Other									(30)
Balance at Dec. 31, 2017	CAD 65,732	CAD 7,747	CAD 50,737	CAD 3,194	CAD (2,468)	CAD (973)	CAD (102)	CAD 58,135	CAD 7,597
Increase (Decrease) in Stockholders' Equity
Dividends paid per common share	CAD 2.41