Disclosure of inventories.

No definition available.

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- Definition

The amount of expense from the write-down of inventory to net realizable value that was realized when the inventory was sold.

+ References

No definition available.

+ Details

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- Definition

The amount of inventories recognised as an expense during the period. [Refer: Inventories]

+ References

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- Definition

The amount of expense recognised related to the write-down of inventories to net realisable value. [Refer: Inventories]

+ References

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- Definition

The amount recognised as a reduction in the amount of inventories recognised as an expense due to the reversal of any write-down of inventories resulting from an increase in net realisable value. [Refer: Inventories; Inventory write-down]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Inventories - Additional Information (Detail) - CAD ($) $ in Millions		12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of inventories [line items]
Cost of inventories recognized as expense during period		$ 9,996	$ 14,285	$ 15,664
Realized inventory write-down	$ 547
Crude Oil Blend, Condensate and Refined Product Inventory [Member]
Disclosure of inventories [line items]
Inventory write-downs	$ 588
Reversed inventory write downs		39
Refined Product Inventory [Member]
Disclosure of inventories [line items]
Inventory write-downs		$ 6	$ 25