Inventories - Schedule of Inventories (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Disclosure of inventories [abstract]
Gold-in-process and stockpiles	$ 325.0	$ 305.4
Consumable stores	176.5	220.9
Total inventories	501.5	526.3
Heap leach and stockpiles inventories included in non-current assets	(133.3)	(132.8)
Total current inventories	$ 368.2	$ 393.5

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 2018-01-01
-Paragraph 54
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_g&doctype=Standard
-URIDate 2018-03-16

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