Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Jul. 25, 2020	Jul. 27, 2019	Jul. 28, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 11,214	$ 11,621	$ 110
Available-for-sale investments:
Change in net unrealized gains and losses, net of tax benefit (expense) of $(84), $(101), and $(11) for fiscal 2020, 2019, and 2018, respectively	336	459	(554)
Net (gains) losses reclassified into earnings, net of tax expense (benefit) of $21, $6, and $104 for fiscal 2020, 2019, and 2018, respectively	(21)	19	(183)
Total Available-for-sale investments	315	478	(737)
Cash flow hedging instruments:
Change in unrealized gains and losses, net of tax benefit (expense) of $0, $0, and $(3) for fiscal 2020, 2019, and 2018, respectively	7
Change in unrealized gains and losses, net of tax benefit (expense) of $0, $0, and $(3) for fiscal 2020, 2019, and 2018, respectively		0	18
Net (gains) losses reclassified into earnings, net of tax (benefit) expense of $0, $0, and $7 for fiscal 2020, 2019, and 2018, respectively	1
Net (gains) losses reclassified into earnings, net of tax (benefit) expense of $0, $0, and $7 for fiscal 2020, 2019, and 2018, respectively		(3)	(61)
Total cash flow hedging instruments	8
Total Cash flow hedging instruments		(3)	(43)
Net change in cumulative translation adjustment and actuarial gains and losses, net of tax benefit (expense) of $(5), $15, and $(8) for fiscal 2020, 2019, and 2018, respectively	(50)	(250)	(160)
Other comprehensive income (loss)	273	225	(940)
Comprehensive income (loss)	$ 11,487	$ 11,846	$ (830)