ACQUISITIONS - Other (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 03, 2018	Jun. 29, 2018	Jun. 28, 2018
Mara Rosa
Acquisitions
Net smelter return (NSR) (as a percent)		1.75%	1.00%
Consideration paid		$ 10.8	$ 10.8
CORE
Acquisitions
Shares acquired	127,188		682,556
Share price	$ 26		$ 26

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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