CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statements of Cash Flow (Details) - CAD ($) $ in Millions	1 Months Ended	6 Months Ended
	Jan. 31, 2019	Jun. 30, 2019	Jun. 30, 2018
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		$ 4,670	$ 6,538
Investing activities
Capital expenditures	$ (265)	(2,785)	(3,243)
Long-term investments and restricted long-term investments		(700)	(611)
Distributions from equity investments in excess of cumulative earnings		268	1,140
Additions to intangible assets		(100)	(425)
Affiliate loans, net		(140)	0
Proceeds from dispositions		0	4
Contributions to subsidiaries		0	0
Return of share capital from subsidiaries		0	0
Advances to affiliates		0	0
Repayment of advances to affiliates		0	0
Other		0	(4)
Net cash used in investing activities		(3,457)	(3,139)
Financing activities
Net change in short-term borrowings		(108)	(433)
Net change in commercial paper and credit facility draws		4,015	(2,166)
Debenture and term note issues, net of issue costs		1,195	3,537
Debenture and term note repayments		(2,584)	(2,147)
Contributions from noncontrolling interests		9	21
Distributions to noncontrolling interests		(100)	(425)
Contributions from redeemable noncontrolling interests		0	41
Distributions to redeemable noncontrolling interests		0	(174)
Contributions from parents		0	0
Distributions to parents		0	0
Redemption of preferred shares held by subsidiary (Note 10)		(300)	0
Common shares issued		18	14
Preference share dividends		(191)	(174)
Common share dividends		(2,976)	(1,493)
Advances from affiliates		0	0
Repayment of advances from affiliates		0	0
Other		(36)	0
Net cash provided by/(used in) financing activities		(1,058)	(3,399)
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		(25)	35
Net increase in cash and cash equivalents and restricted cash		130	35
Cash and cash equivalents and restricted cash at beginning of period	637	637	587
Cash and cash equivalents and restricted cash at end of period		767	622
Consolidation, Eliminations
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		(1,416)	(752)
Investing activities
Capital expenditures		0	0
Long-term investments and restricted long-term investments		0	34
Distributions from equity investments in excess of cumulative earnings		(564)	(1,711)
Additions to intangible assets		0	0
Affiliate loans, net		0	0
Proceeds from dispositions			0
Contributions to subsidiaries		2,339	2,178
Return of share capital from subsidiaries		(4,921)	(1,916)
Advances to affiliates		75,140	5,631
Repayment of advances to affiliates		(15,100)	(4,455)
Other			0
Net cash used in investing activities		56,894	(239)
Financing activities
Net change in short-term borrowings		0	0
Net change in commercial paper and credit facility draws		0	0
Debenture and term note issues, net of issue costs		0	0
Debenture and term note repayments		0	0
Contributions from noncontrolling interests		9	21
Distributions to noncontrolling interests		(100)	(425)
Contributions from redeemable noncontrolling interests		0	41
Distributions to redeemable noncontrolling interests		0	(174)
Contributions from parents		(2,339)	(2,178)
Distributions to parents		6,992	4,882
Redemption of preferred shares held by subsidiary (Note 10)		0
Common shares issued		0	0
Preference share dividends		0	0
Common share dividends		0	0
Advances from affiliates		(75,140)	(5,631)
Repayment of advances from affiliates		15,100	4,455
Other		0	0
Net cash provided by/(used in) financing activities		(55,478)	991
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		0	0
Net increase in cash and cash equivalents and restricted cash		0	0
Cash and cash equivalents and restricted cash at beginning of period	0	0	0
Cash and cash equivalents and restricted cash at end of period		0	0
Parent Issuer and Guarantor | Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		560	(79)
Investing activities
Capital expenditures		(31)	(8)
Long-term investments and restricted long-term investments		(8)	(36)
Distributions from equity investments in excess of cumulative earnings		0	1,260
Additions to intangible assets		(36)	(20)
Affiliate loans, net		0	0
Proceeds from dispositions			0
Contributions to subsidiaries		(2,336)	(2,093)
Return of share capital from subsidiaries		4,921	1,916
Advances to affiliates		(32,520)	(2,324)
Repayment of advances to affiliates		4,748	1,094
Other			0
Net cash used in investing activities		(25,262)	(211)
Financing activities
Net change in short-term borrowings		0	0
Net change in commercial paper and credit facility draws		2,827	(931)
Debenture and term note issues, net of issue costs		0	2,556
Debenture and term note repayments		(1,050)	0
Contributions from noncontrolling interests		0	0
Distributions to noncontrolling interests		0	0
Contributions from redeemable noncontrolling interests		0	0
Distributions to redeemable noncontrolling interests		0	0
Contributions from parents		0	0
Distributions to parents		0	0
Redemption of preferred shares held by subsidiary (Note 10)		0
Common shares issued		18	14
Preference share dividends		(191)	(174)
Common share dividends		(2,976)	(1,493)
Advances from affiliates		33,074	368
Repayment of advances from affiliates		(7,000)	(43)
Other		0	0
Net cash provided by/(used in) financing activities		24,702	297
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		0	0
Net increase in cash and cash equivalents and restricted cash		0	7
Cash and cash equivalents and restricted cash at beginning of period	9	9	2
Cash and cash equivalents and restricted cash at end of period		9	9
Subsidiary Non-Guarantors | Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		4,723	5,639
Investing activities
Capital expenditures		(2,754)	(3,235)
Long-term investments and restricted long-term investments		(688)	(600)
Distributions from equity investments in excess of cumulative earnings		251	1,116
Additions to intangible assets		(64)	(405)
Affiliate loans, net		(140)	0
Proceeds from dispositions			4
Contributions to subsidiaries		0	0
Return of share capital from subsidiaries		0	0
Advances to affiliates		(41,213)	(2,397)
Repayment of advances to affiliates		9,930	1,890
Other			(4)
Net cash used in investing activities		(34,678)	(3,631)
Financing activities
Net change in short-term borrowings		(108)	(433)
Net change in commercial paper and credit facility draws		4,222	(150)
Debenture and term note issues, net of issue costs		1,195	981
Debenture and term note repayments		(345)	(1,638)
Contributions from noncontrolling interests		0	0
Distributions to noncontrolling interests		0	0
Contributions from redeemable noncontrolling interests		0	0
Distributions to redeemable noncontrolling interests		0	0
Contributions from parents		2,339	2,178
Distributions to parents		(5,650)	(3,627)
Redemption of preferred shares held by subsidiary (Note 10)		(300)
Common shares issued		0	0
Preference share dividends		0	0
Common share dividends		0	0
Advances from affiliates		33,927	3,234
Repayment of advances from affiliates		(5,170)	(2,565)
Other		(25)	9
Net cash provided by/(used in) financing activities		30,085	(2,011)
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		(25)	35
Net increase in cash and cash equivalents and restricted cash		105	32
Cash and cash equivalents and restricted cash at beginning of period	612	612	571
Cash and cash equivalents and restricted cash at end of period		717	603
Spectra Energy Partners L P | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		551	1,875
Investing activities
Capital expenditures		0	0
Long-term investments and restricted long-term investments		(4)	(9)
Distributions from equity investments in excess of cumulative earnings		17	24
Additions to intangible assets		0	0
Affiliate loans, net		0	0
Proceeds from dispositions			0
Contributions to subsidiaries		0	(78)
Return of share capital from subsidiaries		0	0
Advances to affiliates		0	0
Repayment of advances to affiliates		0	511
Other			0
Net cash used in investing activities		13	448
Financing activities
Net change in short-term borrowings		0	0
Net change in commercial paper and credit facility draws		(2,017)	(1,397)
Debenture and term note issues, net of issue costs		0	0
Debenture and term note repayments		0	0
Contributions from noncontrolling interests		0	0
Distributions to noncontrolling interests		0	0
Contributions from redeemable noncontrolling interests		0	0
Distributions to redeemable noncontrolling interests		0	0
Contributions from parents		0	0
Distributions to parents		(1,014)	(924)
Redemption of preferred shares held by subsidiary (Note 10)		0
Common shares issued		0	0
Preference share dividends		0	0
Common share dividends		0	0
Advances from affiliates		4,419	0
Repayment of advances from affiliates		(1,949)	0
Other		(5)	(6)
Net cash provided by/(used in) financing activities		(566)	(2,327)
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		0	0
Net increase in cash and cash equivalents and restricted cash		(2)	(4)
Cash and cash equivalents and restricted cash at beginning of period	16	16	14
Cash and cash equivalents and restricted cash at end of period		14	10
Enbridge Energy Partners, L.P. | Subsidiary Issuer and Guarantor - SEP and EEP | Reportable Legal Entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		252	(145)
Investing activities
Capital expenditures		0	0
Long-term investments and restricted long-term investments		0	0
Distributions from equity investments in excess of cumulative earnings		564	451
Additions to intangible assets		0	0
Affiliate loans, net		0	0
Proceeds from dispositions			0
Contributions to subsidiaries		(3)	(7)
Return of share capital from subsidiaries		0	0
Advances to affiliates		(1,407)	(910)
Repayment of advances to affiliates		422	960
Other			0
Net cash used in investing activities		(424)	494
Financing activities
Net change in short-term borrowings		0	0
Net change in commercial paper and credit facility draws		(1,017)	312
Debenture and term note issues, net of issue costs		0	0
Debenture and term note repayments		(1,189)	(509)
Contributions from noncontrolling interests		0	0
Distributions to noncontrolling interests		0	0
Contributions from redeemable noncontrolling interests		0	0
Distributions to redeemable noncontrolling interests		0	0
Contributions from parents		0	0
Distributions to parents		(328)	(331)
Redemption of preferred shares held by subsidiary (Note 10)		0
Common shares issued		0	0
Preference share dividends		0	0
Common share dividends		0	0
Advances from affiliates		3,720	2,029
Repayment of advances from affiliates		(981)	(1,847)
Other		(6)	(3)
Net cash provided by/(used in) financing activities		199	(349)
Effect of translation of foreign denominated cash and cash equivalents and restricted cash		0	0
Net increase in cash and cash equivalents and restricted cash		27	0
Cash and cash equivalents and restricted cash at beginning of period	$ 0	0	0
Cash and cash equivalents and restricted cash at end of period		$ 27	$ 0