COMMITMENTS AND CONTINGENCIES: - Environmental matters (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Environmental costs
Environmental capital investment	$ 91.1	$ 94.8
Peru
Environmental costs
Environmental capital investment	6.9	2.0
Mexico
Environmental costs
Environmental capital investment	$ 84.2	$ 92.8

Amount of environmental remediation costs capitalized. These expenditures may relate to long-lived improvements in operating facilities.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
-Section 25
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482049/410-30-25-18

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