Guarantees (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019	Jul. 31, 2019
Guarantor Obligations
Royalty income	$ 629.7	$ 712.8	$ 1,964.4	$ 2,117.9
Advanced Filtration Systems, Inc.
Guarantor Obligations
Outstanding debt (the Company guarantees half)	39.6		39.6		$ 38.8
Contingent liability for standby letters of credit	7.5		7.5		11.0
Amounts drawn for letters of credit	0.0		0.0		$ 0.0
Investment earnings (loss)	0.8	0.4	1.2	0.1
Advanced Filtration Systems, Inc. \| Royalty
Guarantor Obligations
Royalty income	$ 1.6	$ 1.5	$ 5.2	$ 4.8

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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