Basis of Statement Presentation Other Noncurrent Liabilities (Details) - USD ($) $ in Millions	Apr. 30, 2026	Jul. 31, 2025
Liabilities, Current [Abstract]
Reclamation liability	$ 6.1	$ 5.9
Postretirement health benefits	$ 1.7	$ 1.6

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant