COMMITMENTS, CONTINGENCIES AND GUARANTEES - Guarantees (Details) CAD in Millions	Dec. 31, 2016 CAD	Dec. 31, 2015 CAD guarantee
Guarantees
Number of guarantees without a termination date \| guarantee		1
Contingent financial obligation
Guarantees
Potential Exposure	CAD 980	CAD 227
Carrying Value	82	26
Contingent financial obligation \| Sur de Texas
Guarantees
Potential Exposure	805	0
Carrying Value	53	0
Contingent financial obligation \| Bruce Power
Guarantees
Potential Exposure	88	88
Carrying Value	1	2
Contingent financial obligation \| Other jointly owned entities
Guarantees
Potential Exposure	87	139
Carrying Value	CAD 28	CAD 24

Guarantor Obligations, Number of Guarantees Without a Termination Date

No definition available.

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Namespace Prefix:	trp_
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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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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.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Details

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- Details

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- Details

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