CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY $ in Millions, $ in Millions	CAD ($) $ / shares	Preferred share investment CAD ($)	Common shares CAD ($)	Additional paid-in capital USD ($)	Additional paid-in capital CAD ($)	Retained earnings/(deficit) CAD ($)	Accumulated other comprehensive income CAD ($)	Reciprocal shareholding CAD ($)	Total Enbridge Inc. shareholders' equity CAD ($)	Noncontrolling interests CAD ($)
Balance at Dec. 31, 2017		$ 7,747	$ 50,737		$ 3,194	$ (2,468)	$ (973)	$ (102)		$ 7,597
Increase (Decrease) in Stockholders' Equity
Dividend Reinvestment and Share Purchase Plan			374
Options exercised			16		(6)
Stock-based compensation					17
Dilution gain on Spectra Energy Partners, LP restructuring					1,136
Dilution loss and other					(28)
Earnings attributable to controlling interests	$ 534					534
Preference share dividends						(89)
Dividends paid to reciprocal shareholder						7
Redemption value adjustment attributable to redeemable noncontrolling interests						120
Other										(15)
Other comprehensive income/(loss) attributable to common shareholders, net of tax							1,302
Earnings attributable to noncontrolling interests										23
Change in unrealized gain/(loss) on cash flow hedges										4
Foreign currency translation adjustments										152
Reclassification to earnings of loss on cash flow hedges										8
Other comprehensive income/(loss) attributable to noncontrolling interests, net of tax										164
Comprehensive income attributable to noncontrolling interests										187
Spectra Energy Partners, LP restructuring										(1,486)
Contributions										8
Distributions										(209)
Balance at Mar. 31, 2018	$ 67,514	7,747	51,127		4,313	(1,982)	329	(102)	$ 61,432	6,082
Increase (Decrease) in Stockholders' Equity
Dividends paid per common share (in Canadian dollars per share) | $ / shares	$ 0.671
Earnings per common share attributable to common shareholders (Note 5) (in Canadian dollars per share) | $ / shares	0.26
Diluted earnings per common share attributable to common shareholders (Note 5) (in Canadian dollars per share) | $ / shares	$ 0.26
Balance at Dec. 31, 2018	$ 73,435	7,747	64,677	$ 0		(5,538)	2,672	(88)		3,965
Increase (Decrease) in Stockholders' Equity
Options exercised			51		(43)
Stock-based compensation					4
Change in reciprocal interest					109
Dilution loss and other					2
Earnings attributable to controlling interests	1,986					1,986
Preference share dividends						(95)
Dividends paid to reciprocal shareholder						5
Other						2	55			5
Other comprehensive income/(loss) attributable to common shareholders, net of tax							(1,278)
Change in reciprocal interest								37
Earnings attributable to noncontrolling interests										37
Change in unrealized gain/(loss) on cash flow hedges										(1)
Foreign currency translation adjustments										(49)
Reclassification to earnings of loss on cash flow hedges										0
Other comprehensive income/(loss) attributable to noncontrolling interests, net of tax										(50)
Comprehensive income attributable to noncontrolling interests										(13)
Contributions										3
Distributions										(46)
Redemption of preferred shares held by subsidiary (Note 10)										(300)
Balance at Mar. 31, 2019	$ 73,919	$ 7,747	$ 64,728		$ 72	$ (3,640)	$ 1,449	$ (51)	$ 70,305	$ 3,614
Increase (Decrease) in Stockholders' Equity
Dividends paid per common share (in Canadian dollars per share) | $ / shares	$ 0.738
Earnings per common share attributable to common shareholders (Note 5) (in Canadian dollars per share) | $ / shares	0.94
Diluted earnings per common share attributable to common shareholders (Note 5) (in Canadian dollars per share) | $ / shares	$ 0.94