Leases - Operating Lease Assets (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Leases [Abstract]
Operating lease assets	$ 205	$ 273
Accumulated depreciation	(119)	(165)
Operating lease assets, net	$ 86	$ 108

Amount of accumulated depreciation of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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