INVENTORY (Details) (CAD) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INVENTORY
Natural gas	678	527
Other commodities	470us-gaap_OtherInventoryNetOfReserves	588us-gaap_OtherInventoryNetOfReserves
Inventory, Net, Total	1,148us-gaap_InventoryNet	1,115us-gaap_InventoryNet
Non-cash charges to reduce the cost basis of inventory to market value	174us-gaap_InventoryWriteDown	4us-gaap_InventoryWriteDown	10us-gaap_InventoryWriteDown

Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale.

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- Details

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

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- Definition

Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

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- Definition

Carrying amount, net of valuation reserves and allowances, as of the balance sheet date of inventories not otherwise specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.BB)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Article 5

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+ Details

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