Inventories - Summary of Inventories (Detail) - CAD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Inventories [Abstract]
Supplies	$ 757	$ 721
Raw materials	197	271
Work in process	592	491
Finished products	410	573
Inventories	1,956	2,056
Less long-term portion (Note 14)	(84)	(75)
Current inventories	$ 1,872	$ 1,981

The amount of assets: (a) held for sale in the ordinary course of business; (b) in the process of production for such sale; or (c) in the form of materials or supplies to be consumed in the production process or in the rendering of services. Inventories encompass goods purchased and held for resale including, for example, merchandise purchased by a retailer and held for resale, or land and other property held for resale. Inventories also encompass finished goods produced, or work in progress being produced, by the entity and include materials and supplies awaiting use in the production process. [Refer: Current finished goods; Current merchandise; Current work in progress; Land]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 54
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_54_g&doctype=Standard
-URIDate 2020-01-01

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