Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 25, 2020	Jan. 26, 2019	Jan. 25, 2020	Jan. 26, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 2,878	$ 2,822	$ 5,804	$ 6,371
Available-for-sale investments:
Change in net unrealized gains and losses, net of tax benefit (expense) of $(15) and $(29) for the second quarter and first six months of fiscal 2020, respectively, and $(12) and $1 for the corresponding periods of fiscal 2019, respectively	66	82	139	87
Net (gains) losses reclassified into earnings, net of tax (benefit) expense of $7 and $12 for the second quarter and first six months of fiscal 2020, respectively, and $(1) for each of the corresponding periods of fiscal 2019, respectively	(4)	4	(9)	10
Total- Available-for-sale investments	62	86	130	97
Cash flow hedging instruments:
Change in unrealized gains and losses, net of tax benefit (expense) of $0 and $1 for the second quarter and first six months of fiscal 2020, respectively, and $1 and $2 for the corresponding periods of fiscal 2019, respectively	1		1
Change in unrealized gains and losses, net of tax benefit (expense) of $0 and $1 for the second quarter and first six months of fiscal 2020, respectively, and $1 and $2 for the corresponding periods of fiscal 2019, respectively		(4)		(7)
Net (gains) losses reclassified into earnings, net of tax (benefit) expense of $0 for each of the respective periods	2		2
Net (gains) losses reclassified into earnings, net of tax (benefit) expense of $0 for each of the respective periods		(1)		(1)
Total- Cash flow hedging instruments	3		3
Total- Cash flow hedging instruments		(5)		(8)
Net change in cumulative translation adjustment and actuarial gains and losses net of tax benefit (expense) of $(1) for each of the second quarter and first six months of fiscal 2020, respectively, and $0 and $(1) for the corresponding periods of fiscal 2019, respectively	50	27	(41)	(182)
Other comprehensive income (loss)	115	108	92	(93)
Comprehensive income	$ 2,993	$ 2,930	$ 5,896	$ 6,278