CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Earnings and Comprehensive Income (Details) - CAD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating revenues
Revenues	$ 13,263	$ 10,745	$ 26,119	$ 23,471
Operating expenses
Operating and administrative	1,695	1,636	3,320	3,277
Depreciation and amortization	842	829	1,682	1,653
Impairment of long-lived assets	0	10	0	1,072
Total operating expenses	10,978	9,174	21,215	21,022
Operating income	2,285	1,571	4,904	2,449
Income from equity investments	413	363	826	698
Equity earnings from consolidated subsidiaries	0	0	0	0
Other
Net foreign currency gain/(loss)	140	(43)	354	(228)
Other	65	29	111	94
Interest expense	(637)	(690)	(1,322)	(1,346)
Earnings before income taxes	2,266	1,230	4,873	1,667
Income tax recovery/(expense)	(436)	97	(1,020)	170
Earnings	1,830	1,327	3,853	1,837
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	2	(167)	(35)	(143)
Earnings attributable to controlling interests	1,832	1,160	3,818	1,694
Preference share dividends	(96)	(89)	(191)	(178)
Earnings attributable to common shareholders	1,736	1,071	3,627	1,516
Total other comprehensive income/(loss)	(1,374)	1,078	(2,702)	2,551
Comprehensive income	456	2,405	1,151	4,388
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	51	(297)	64	(444)
Comprehensive income attributable to controlling interests	507	2,108	1,215	3,944
Consolidation, Eliminations
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	0	0	0	0
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets		0		0
Total operating expenses	0	0	0	0
Operating income	0	0	0	0
Income from equity investments	(6)	(55)	(65)	(71)
Equity earnings from consolidated subsidiaries	(2,692)	(2,660)	(4,620)	(4,729)
Other
Net foreign currency gain/(loss)	(143)	61	(1,047)	131
Other	(565)	(276)	(1,013)	(527)
Interest expense	595	282	1,053	556
Earnings before income taxes	(2,811)	(2,648)	(5,692)	(4,640)
Income tax recovery/(expense)	106	9	212	18
Earnings	(2,705)	(2,639)	(5,480)	(4,622)
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	2	(167)	(35)	(143)
Earnings attributable to controlling interests	(2,703)	(2,806)	(5,515)	(4,765)
Preference share dividends	0	0	0	0
Earnings attributable to common shareholders	(2,703)	(2,806)	(5,515)	(4,765)
Total other comprehensive income/(loss)	113	(49)	784	(158)
Comprehensive income	(2,592)	(2,688)	(4,696)	(4,780)
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	51	(297)	64	(444)
Comprehensive income attributable to controlling interests	(2,541)	(2,985)	(4,632)	(5,224)
Parent Issuer and Guarantor | Reportable Legal Entities
Operating revenues
Revenues	0	0	0	0
Operating expenses
Operating and administrative	69	33	35	100
Depreciation and amortization	18	15	33	29
Impairment of long-lived assets		0		0
Total operating expenses	87	48	68	129
Operating income	(87)	(48)	(68)	(129)
Income from equity investments	8	59	67	76
Equity earnings from consolidated subsidiaries	1,624	1,287	2,398	1,994
Other
Net foreign currency gain/(loss)	256	(171)	1,477	(370)
Other	464	272	794	518
Interest expense	(322)	(286)	(630)	(529)
Earnings before income taxes	1,943	1,113	4,038	1,560
Income tax recovery/(expense)	(111)	47	(220)	134
Earnings	1,832	1,160	3,818	1,694
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	1,832	1,160	3,818	1,694
Preference share dividends	(96)	(89)	(191)	(178)
Earnings attributable to common shareholders	1,736	1,071	3,627	1,516
Total other comprehensive income/(loss)	(1,325)	948	(2,603)	2,250
Comprehensive income	507	2,108	1,215	3,944
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income attributable to controlling interests	507	2,108	1,215	3,944
Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	13,263	10,745	26,119	23,471
Operating expenses
Operating and administrative	1,627	1,595	3,283	3,164
Depreciation and amortization	824	814	1,649	1,624
Impairment of long-lived assets		10		1,072
Total operating expenses	10,892	9,118	21,145	20,880
Operating income	2,371	1,627	4,974	2,591
Income from equity investments	380	323	762	623
Equity earnings from consolidated subsidiaries	473	615	966	1,223
Other
Net foreign currency gain/(loss)	27	65	(76)	7
Other	112	(3)	235	36
Interest expense	(690)	(477)	(1,273)	(956)
Earnings before income taxes	2,673	2,150	5,588	3,524
Income tax recovery/(expense)	(443)	41	(1,039)	18
Earnings	2,230	2,191	4,549	3,542
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	2,230	2,191	4,549	3,542
Preference share dividends	0	0	0	0
Earnings attributable to common shareholders	2,230	2,191	4,549	3,542
Total other comprehensive income/(loss)	(148)	162	(868)	415
Comprehensive income	2,082	2,353	3,681	3,957
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income attributable to controlling interests	2,082	2,353	3,681	3,957
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	3	3	4
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets		0		0
Total operating expenses	1	3	3	4
Operating income	(1)	(3)	(3)	(4)
Income from equity investments	31	36	62	70
Equity earnings from consolidated subsidiaries	344	529	742	1,080
Other
Net foreign currency gain/(loss)	0	2	0	4
Other	1	1	1	2
Interest expense	(84)	(72)	(178)	(144)
Earnings before income taxes	291	493	624	1,008
Income tax recovery/(expense)	12	0	27	0
Earnings	303	493	651	1,008
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	303	493	651	1,008
Preference share dividends	0	0	0	0
Earnings attributable to common shareholders	303	493	651	1,008
Total other comprehensive income/(loss)	(28)	11	(44)	30
Comprehensive income	275	504	607	1,038
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income attributable to controlling interests	275	504	607	1,038
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	(2)	5	(1)	9
Depreciation and amortization	0	0	0	0
Impairment of long-lived assets		0		0
Total operating expenses	(2)	5	(1)	9
Operating income	2	(5)	1	(9)
Income from equity investments	0	0	0	0
Equity earnings from consolidated subsidiaries	251	229	514	432
Other
Net foreign currency gain/(loss)	0	0	0	0
Other	53	35	94	65
Interest expense	(136)	(137)	(294)	(273)
Earnings before income taxes	170	122	315	215
Income tax recovery/(expense)	0	0		0
Earnings	170	122	315	215
(Earnings)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Earnings attributable to controlling interests	170	122	315	215
Preference share dividends	0	0	0	0
Earnings attributable to common shareholders	170	122	315	215
Total other comprehensive income/(loss)	14	6	29	14
Comprehensive income	184	128	344	229
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	0	0	0	0
Comprehensive income attributable to controlling interests	184	128	344	229
Commodity
Operating revenues
Revenues	8,416	6,451	15,048	13,719
Operating expenses
Cost of goods and services sold	8,129	6,278	14,694	13,275
Commodity | Consolidation, Eliminations
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Commodity | 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 | Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	8,416	6,451	15,048	13,719
Operating expenses
Cost of goods and services sold	8,129	6,278	14,694	13,275
Commodity | 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 | 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
Operating revenues
Revenues	755	856	2,631	2,782
Operating expenses
Cost of goods and services sold	312	421	1,519	1,745
Gas Distribution | Consolidation, Eliminations
Operating revenues
Revenues	0	0	0	0
Operating expenses
Cost of goods and services sold	0	0	0	0
Gas Distribution | 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 | Subsidiary Non-Guarantors | Reportable Legal Entities
Operating revenues
Revenues	755	856	2,631	2,782
Operating expenses
Cost of goods and services sold	312	421	1,519	1,745
Gas Distribution | 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 | 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	4,092	3,438	8,440	6,970
Transportation and other services | Consolidation, Eliminations
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	4,092	3,438	8,440	6,970
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