Guarantees (Details) - USD ($)	12 Months Ended
Jul. 31, 2026	Jul. 31, 2025
Guarantor Obligations
Loss contingency accrual	$ 8,400,000	$ 7,900,000
Letters of credit outstanding, amount	0	0
AFSI outstanding debt	1,300,000,000
Advanced Filtration Systems Inc.
Guarantor Obligations
Investment earnings	13,700,000	12,900,000
Unsecured Revolving Credit Facility
Guarantor Obligations
Available credit facilities	63,000,000.0
Multi-currency revolving credit facility
Guarantor Obligations
Available credit facilities	17,000,000.0
Advanced Filtration Systems Inc.
Guarantor Obligations
AFSI outstanding debt	$ 31,900,000	$ 43,900,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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