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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Commitments and Contingencies (Principal Risks and Uncertainties) (Details) CAD in Millions, $ in Billions	Jul. 01, 2016 CAD	Jul. 01, 2016 USD ($)	Dec. 31, 2016 CAD	Dec. 31, 2015 CAD
Loss Contingencies [Line Items]
Public Utilities, Property, Plant and Equipment, Net			CAD 15,886	CAD 6,258
Total Debt			CAD 15,000
TECO Energy Inc [Member]
Loss Contingencies [Line Items]
Business Combination, Consideration Transferred	CAD 13,900	$ 10.7