Derivative instruments and hedging activities - Margin Balances (Details) - USD ($) $ in Thousands	Oct. 31, 2023	Jul. 31, 2023
Derivative instruments and hedging activities
Derivative Asset, Fair Value of Collateral	$ 14,707	$ 13,904
Derivative Liability, Fair Value of Collateral	2,436	6,972
Prepaid Expenses and Other Current Assets
Derivative instruments and hedging activities
Derivative Asset, Fair Value of Collateral	13,918	11,939
Other Current Liabilities
Derivative instruments and hedging activities
Derivative Liability, Fair Value of Collateral	2,424	6,972
Other Assets, Net
Derivative instruments and hedging activities
Derivative Asset, Fair Value of Collateral	789	$ 1,965
Other Liabilities
Derivative instruments and hedging activities
Derivative Liability, Fair Value of Collateral	$ 12

Fair value of securities received as collateral against derivative assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-12

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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