Income Taxes - Sources of income from continuing operations (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Income Tax Disclosure [Abstract]
United States	$ 2,433	$ 2,497	$ 2,206
Foreign	109	59	(8)
Income before income taxes	$ 2,542	$ 2,556	$ 2,198