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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Guarantees (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Guarantees (Details) - USD ($) $ in Millions	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021	Jul. 31, 2021
Guarantor Obligations
Contingent liability for standby letters of credit issued under the Company’s revolving credit facility	$ 7.5		$ 7.5		$ 7.7
Amounts drawn for letters of credit under the Company’s revolving credit facility	0.0		0.0		0.0
Investment earnings	2.0	$ 1.9	3.2	$ 3.7
Revolving credit facility
Guarantor Obligations
AFSI outstanding debt (the Company guarantees half)	63.0		63.0
Advanced Filtration Systems, Inc.
Guarantor Obligations
AFSI outstanding debt (the Company guarantees half)	$ 46.0		$ 46.0		$ 37.8