CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Earnings and Comprehensive Income (Details) - CAD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating revenues
Revenues	$ 11,598	$ 11,345	$ 37,717	$ 34,816
Operating expenses
Operating and administrative	1,741	1,652	5,061	4,929
Depreciation and amortization	844	799	2,526	2,452
Impairment of long-lived assets	105	4	105	1,076
Impairment of goodwill	0	1,019	0	1,019
Total operating expenses	10,010	10,491	31,225	31,513
Operating income/(loss)	1,588	854	6,492	3,303
Income from equity investments	333	378	1,159	1,076
Equity earnings from consolidated subsidiaries	0	0	0	0
Other
Net foreign currency (loss)/gain	(43)	57	311	(171)
Other, including other income/(expense) from affiliates	81	(33)	192	61
Interest expense	(644)	(696)	(1,966)	(2,042)
Earnings before income taxes	1,315	560	6,188	2,227
Income tax recovery/(expense)	(255)	(347)	(1,275)	(177)
Earnings	1,060	213	4,913	2,050
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	(15)	(209)	(50)	(352)
Earnings attributable to controlling interests	1,045	4	4,863	1,698
Preference share dividends	(96)	(94)	(287)	(272)
Earnings/(loss) attributable to common shareholders	949	(90)	4,576	1,426
Total other comprehensive income/(loss)	491	(814)	(2,211)	1,737
Comprehensive income/(loss)	1,551	(601)	2,702	3,787
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	(41)	(102)	23	(546)
Comprehensive income/(loss) attributable to controlling interests	1,510	(703)	2,725	3,241
Consolidating and elimination adjustments
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	0	(20)	0	(20)
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets	0	0	0	0
Impairment of goodwill		0		0
Total operating expenses	0	(20)	0	(20)
Operating income/(loss)	0	20	0	20
Income from equity investments	(1)	(311)	(66)	(382)
Equity earnings from consolidated subsidiaries	(2,140)	(1,106)	(6,760)	(5,835)
Other
Net foreign currency (loss)/gain	119	(23)	(928)	108
Other, including other income/(expense) from affiliates	(654)	(232)	(1,667)	(759)
Interest expense	659	216	1,712	772
Earnings before income taxes	(2,017)	(1,436)	(7,709)	(6,076)
Income tax recovery/(expense)	92	(33)	304	(15)
Earnings	(1,925)	(1,469)	(7,405)	(6,091)
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	(15)	(209)	(50)	(352)
Earnings attributable to controlling interests	(1,940)	(1,678)	(7,455)	(6,443)
Preference share dividends	0	0	0	0
Earnings/(loss) attributable to common shareholders	(1,940)	(1,678)	(7,455)	(6,443)
Total other comprehensive income/(loss)	(98)	26	686	(132)
Comprehensive income/(loss)	(2,023)	(1,443)	(6,719)	(6,223)
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	(41)	(102)	23	(546)
Comprehensive income/(loss) attributable to controlling interests	(2,064)	(1,545)	(6,696)	(6,769)
Parent Issuer and Guarantor | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	69	56	104	156
Depreciation and amortization	15	15	48	44
Impairment of long-lived assets	0	0	0	0
Impairment of goodwill		0		0
Total operating expenses	84	71	152	200
Operating income/(loss)	(84)	(71)	(152)	(200)
Income from equity investments	2	312	69	388
Equity earnings from consolidated subsidiaries	1,109	(272)	3,507	1,722
Other
Net foreign currency (loss)/gain	(163)	97	1,314	(273)
Other, including other income/(expense) from affiliates	512	214	1,306	732
Interest expense	(299)	(272)	(929)	(801)
Earnings before income taxes	1,077	8	5,115	1,568
Income tax recovery/(expense)	(32)	(4)	(252)	130
Earnings	1,045	4	4,863	1,698
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	1,045	4	4,863	1,698
Preference share dividends	(96)	(94)	(287)	(272)
Earnings/(loss) attributable to common shareholders	949	(90)	4,576	1,426
Total other comprehensive income/(loss)	465	(707)	(2,138)	1,543
Comprehensive income/(loss)	1,510	(703)	2,725	3,241
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income/(loss) attributable to controlling interests	1,510	(703)	2,725	3,241
Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	11,598	11,345	37,717	34,816
Operating expenses
Operating and administrative	1,670	1,604	4,953	4,768
Depreciation and amortization	829	784	2,478	2,408
Impairment of long-lived assets	105	4	105	1,076
Impairment of goodwill		1,019		1,019
Total operating expenses	9,924	10,428	31,069	31,308
Operating income/(loss)	1,674	917	6,648	3,508
Income from equity investments	297	339	1,059	962
Equity earnings from consolidated subsidiaries	451	613	1,417	1,836
Other
Net foreign currency (loss)/gain	1	(15)	(75)	(8)
Other, including other income/(expense) from affiliates	177	(57)	412	(21)
Interest expense	(786)	(423)	(2,059)	(1,379)
Earnings before income taxes	1,814	1,374	7,402	4,898
Income tax recovery/(expense)	(325)	(309)	(1,364)	(291)
Earnings	1,489	1,065	6,038	4,607
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	1,489	1,065	6,038	4,607
Preference share dividends	0	0	0	0
Earnings/(loss) attributable to common shareholders	1,489	1,065	6,038	4,607
Total other comprehensive income/(loss)	162	(163)	(706)	252
Comprehensive income/(loss)	1,651	902	5,332	4,859
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income/(loss) attributable to controlling interests	1,651	902	5,332	4,859
Spectra Energy Partners L P | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	1	8	4	12
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets	0	0	0	0
Impairment of goodwill		0		0
Total operating expenses	1	8	4	12
Operating income/(loss)	(1)	(8)	(4)	(12)
Income from equity investments	35	38	97	108
Equity earnings from consolidated subsidiaries	284	527	1,026	1,607
Other
Net foreign currency (loss)/gain	0	(2)	0	2
Other, including other income/(expense) from affiliates	0	0	1	2
Interest expense	(79)	(77)	(257)	(221)
Earnings before income taxes	239	478	863	1,486
Income tax recovery/(expense)	10	0	37	0
Earnings	249	478	900	1,486
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	249	478	900	1,486
Preference share dividends	0	0	0	0
Earnings/(loss) attributable to common shareholders	249	478	900	1,486
Total other comprehensive income/(loss)	(46)	15	(90)	45
Comprehensive income/(loss)	203	493	810	1,531
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income/(loss) attributable to controlling interests	203	493	810	1,531
Enbridge Energy Partners, L.P. | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	1	4	0	13
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets	0	0	0	0
Impairment of goodwill		0		0
Total operating expenses	1	4	0	13
Operating income/(loss)	(1)	(4)	0	(13)
Income from equity investments	0	0	0	0
Equity earnings from consolidated subsidiaries	296	238	810	670
Other
Net foreign currency (loss)/gain	0	0	0	0
Other, including other income/(expense) from affiliates	46	42	140	107
Interest expense	(139)	(140)	(433)	(413)
Earnings before income taxes	202	136	517	351
Income tax recovery/(expense)	0	(1)	0	(1)
Earnings	202	135	517	350
Earnings attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	202	135	517	350
Preference share dividends	0	0	0	0
Earnings/(loss) attributable to common shareholders	202	135	517	350
Total other comprehensive income/(loss)	8	15	37	29
Comprehensive income/(loss)	210	150	554	379
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income/(loss) attributable to controlling interests	210	150	554	379
Commodity sales
Operating revenues
Revenues	7,396	6,919	22,444	20,638
Operating expenses
Cost of goods and services sold	7,216	6,905	21,910	20,180
Commodity sales | Consolidating and elimination adjustments
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Commodity sales | Parent Issuer and Guarantor | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Commodity sales | Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	7,396	6,919	22,444	20,638
Operating expenses
Cost of goods and services sold	7,216	6,905	21,910	20,180
Commodity sales | Spectra Energy Partners L P | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Commodity sales | Enbridge Energy Partners, L.P. | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Gas distribution revenue
Operating revenues
Revenues	454	478	3,085	3,260
Operating expenses
Cost of goods and services sold	104	112	1,623	1,857
Gas distribution revenue | Consolidating and elimination adjustments
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Gas distribution revenue | Parent Issuer and Guarantor | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Gas distribution revenue | Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	454	478	3,085	3,260
Operating expenses
Cost of goods and services sold	104	112	1,623	1,857
Gas distribution revenue | Spectra Energy Partners L P | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Gas distribution revenue | Enbridge Energy Partners, L.P. | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Transportation and other services
Operating revenues
Revenues	3,748	3,948	12,188	10,918
Transportation and other services | Consolidating and elimination adjustments
Operating revenues
Revenues	0	0	0	0
Transportation and other services | Parent Issuer and Guarantor | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Transportation and other services | Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	3,748	3,948	12,188	10,918
Transportation and other services | Spectra Energy Partners L P | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Transportation and other services | Enbridge Energy Partners, L.P. | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Operating revenues
Revenues	$ 0	$ 0	$ 0	$ 0