COMPONENTS OF ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of accumulated other comprehensive loss
Balance	$ 73,435	$ 65,732
Other comprehensive income/(loss) retained in AOCI	(3,296)	3,479	$ (2,137)
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	17	16	41
Other comprehensive (income)/loss reclassified to earnings	(3,121)	3,680	(1,908)
Income tax on amounts retained in AOCI	164	148	(30)
Income tax on amounts reclassified to earnings	(35)	(41)	(93)
Tax impact	129	107	(123)
Other	48	(142)
Balance	69,407	73,435	65,732
Interest rate contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	157	157	207
Commodity contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	(1)	(1)	(7)
Forward exchange contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	5	7	(6)
Other contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	(3)	22	(6)
Cash Flow Hedges
Components of accumulated other comprehensive loss
Balance	(770)	(644)	(746)
Other comprehensive income/(loss) retained in AOCI	(599)	(244)	1
Changes in AOCI
Other comprehensive (income)/loss reclassified to earnings	(441)	(59)	189
Income tax on amounts retained in AOCI	169	57	(16)
Income tax on amounts reclassified to earnings	(31)	(37)	(71)
Tax impact	138	20	(87)
Other		(87)
Balance	(1,073)	(770)	(644)
Cash Flow Hedges \| Interest rate contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	157	157	207
Cash Flow Hedges \| Commodity contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	(1)	(1)	(7)
Cash Flow Hedges \| Forward exchange contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	5	7	(6)
Cash Flow Hedges \| Other contracts
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	(3)	22	(6)
Net Investment Hedges
Components of accumulated other comprehensive loss
Balance	(598)	(139)	(629)
Other comprehensive income/(loss) retained in AOCI	320	(509)	478
Changes in AOCI
Other comprehensive (income)/loss reclassified to earnings	320	(509)	478
Income tax on amounts retained in AOCI	(39)	50	12
Tax impact	(39)	50	12
Balance	(317)	(598)	(139)
Cumulative Translation Adjustment
Components of accumulated other comprehensive loss
Balance	4,323	77	2,700
Other comprehensive income/(loss) retained in AOCI	(2,927)	4,301	(2,623)
Changes in AOCI
Other comprehensive (income)/loss reclassified to earnings	(2,927)	4,301	(2,623)
Other		(55)
Balance	1,396	4,323	77
Equity Investees
Components of accumulated other comprehensive loss
Balance	34	10	37
Other comprehensive income/(loss) retained in AOCI	34	16	(11)
Changes in AOCI
Other comprehensive (income)/loss reclassified to earnings	34	16	(11)
Income tax on amounts retained in AOCI	6	8	(16)
Tax impact	6	8	(16)
Other	(7)
Balance	67	34	10
Pension and OPEB Adjustment
Components of accumulated other comprehensive loss
Balance	(317)	(277)	(304)
Other comprehensive income/(loss) retained in AOCI	(124)	(85)	18
Changes in AOCI
Amortization of pension and OPEB actuarial loss and prior service costs	17	16	41
Other comprehensive (income)/loss reclassified to earnings	(107)	(69)	59
Income tax on amounts retained in AOCI	28	33	(10)
Income tax on amounts reclassified to earnings	(4)	(4)	(22)
Tax impact	24	29	(32)
Other	55	0
Balance	(345)	(317)	(277)
Total
Components of accumulated other comprehensive loss
Balance	2,672	(973)	1,058
Changes in AOCI
Balance	$ (272)	$ 2,672	$ (973)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

Name:	us-gaap_AOCIAttributableToParentNetOfTaxRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before tax and reclassification adjustments of other comprehensive income (loss).

+ References

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

+ References

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before tax, after reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33775-111570

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e39076-109324

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580

+ Details

Name:	us-gaap_OtherComprehensiveIncomeLossTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase (decrease) in other comprehensive income, after tax, from changes classified as other.

+ References

No definition available.

+ Details

Name:	us-gaap_OtherComprehensiveIncomeOtherNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount before tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 17B
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL34724394-108580

+ Details

Name:	us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 17A
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL34724391-108580

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e39076-109324

+ Details

Name:	us-gaap_ReclassificationFromAociCurrentPeriodTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4568740-111683

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4I
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4590271-111686

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4568447-111683

+ Details

Name:	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CommodityContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_OtherContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedGainLossCashFlowHedgeIncludingNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=enb_AccumulatedNetGainLossNetInvestmentHedgeIncludingNoncontollingInterestMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: