COMMITMENTS, CONTINGENCIES AND GUARANTEES - Guarantees (Details) CAD in Millions	Dec. 31, 2015 CAD guarantee	Dec. 31, 2014 CAD guarantee
Guarantees
Number of guarantees without a termination date \| guarantee	1	1
Contingent financial obligation
Guarantees
Potential Exposure	CAD 227	CAD 738
Carrying Value	26	20
Contingent financial obligation \| Bruce Power
Guarantees
Potential Exposure	88	634
Carrying Value	2	6
Contingent financial obligation \| Other
Guarantees
Potential Exposure	139	104
Carrying Value	CAD 24	CAD 14

Guarantor Obligations, Number of Guarantees Without a Termination Date

No definition available.

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Namespace Prefix:	trp_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- 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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Balance Type:	credit
Period Type:	instant

- 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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