INVENTORY (Details) - CAD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Natural gas	$ 696	$ 776
Crude oil	542	482
Other commodities	61	81
Total	1,299	1,339
Inventory adjustments	$ 188	$ 327	$ 58

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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Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

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

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

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