Number of shares of equity interest issued or to be issued for each outstanding share of common stock of the acquiree.

No definition available.

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- Definition

The pro forma earnings before interest and income taxes for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

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- Definition

This element represents the amount of earnings before interest and income taxes of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

No definition available.

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- 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.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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-Publisher FASB
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-SubTopic 10
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-Paragraph 23
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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 13
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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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ACQUISITIONS AND DISPOSITIONS - Acquisitions (Narrative) (Details) CAD in Millions			9 Months Ended	10 Months Ended	12 Months Ended
	Feb. 27, 2017 CAD shares	Apr. 01, 2016 CAD	Dec. 31, 2016 CAD	Dec. 31, 2017 CAD	Dec. 31, 2017 CAD reporting_unit	Dec. 31, 2016 CAD	Dec. 31, 2015 CAD	Feb. 27, 2017 $ / shares
Business Acquisition [Line Items]
Number of reporting units \| reporting_unit					2
Cash consideration					CAD 0	CAD 644	CAD 106
Spectra Energy
Business Acquisition [Line Items]
Purchase price	CAD 37,509
Shares paid to acquiree for each share of acquiree stock (in shares) \| shares	0.984
Ownership interest acquired (as a percent)								100.00%
Cash paid in lieu of fractional shares	CAD 3
Acquisition-related expenses/transaction costs incurred				CAD 231	231
Costs incurred					180	51
Revenues generated by acquiree				5,740
Earnings generated by acquiree				CAD 2,574
Cash consideration	CAD 3
Pro forma revenues					CAD 45,669	40,934
Tupper Main and Tupper West
Business Acquisition [Line Items]
Acquisition-related expenses/transaction costs incurred		CAD 1
Revenues generated by acquiree			CAD 33
Cash consideration		CAD 539
Earnings before interest and income taxes of acquiree			CAD 22
Pro forma revenues						44
Pro forma earnings before interest and income taxes						CAD 28
Common shares \| Spectra Energy
Business Acquisition [Line Items]
Shares paid as consideration (in shares) \| shares	691,000,000
Share price (in USD per share) \| $ / shares								$ 41.34
Value of shares issued	CAD 37,429
Share options \| Spectra Energy
Business Acquisition [Line Items]
Shares paid as consideration (in shares) \| shares	3,500,000
Value of shares issued	CAD 77
Gas Transmission and Midstream
Business Acquisition [Line Items]
Number of reporting units \| reporting_unit					2