Financing Receivables - Summary of Allowances for Credit Loss and Related Financing Receivables (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 23, 2021	Jan. 25, 2020	Jan. 23, 2021	Jan. 25, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss as of beginning of period	$ 154	$ 133	$ 138	$ 126
Provisions (benefits)	(8)	14	(9)	38
Recoveries (write-offs), net		(2)		(18)
Foreign exchange and other	2	0	19	(1)
Allowance for credit loss as of end of period	148	145	148	145
Lease Receivables
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss as of beginning of period	46	43	48	46
Provisions (benefits)	(4)	(1)	(7)	(4)
Recoveries (write-offs), net		(1)		(1)
Foreign exchange and other	1	1	2	1
Allowance for credit loss as of end of period	43	42	43	42
Loan Receivables
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss as of beginning of period	101	81	81	71
Provisions (benefits)	(6)	15	(3)	42
Recoveries (write-offs), net		(1)		(17)
Foreign exchange and other	1	0	18	(1)
Allowance for credit loss as of end of period	96	95	96	95
Financed Service Contracts
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss as of beginning of period	7	9	9	9
Provisions (benefits)	2	0	1	0
Recoveries (write-offs), net		0		0
Foreign exchange and other	0	(1)	(1)	(1)
Allowance for credit loss as of end of period	$ 9	$ 8	$ 9	$ 8