Income Taxes - Sources of income from continuing operations (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Income Tax Disclosure [Abstract]
United States	$ 2,206	$ 1,826	$ 1,528
Foreign	(8)	55	38
Income before income taxes	$ 2,198	$ 1,881	$ 1,566

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

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