Financing Receivables and Operating Leases - Schedule of Financing Receivables (Details) - USD ($) $ in Millions	Jul. 27, 2019	Jul. 28, 2018	Jul. 29, 2017	Jul. 30, 2016
Financing Receivables [Line Items]
Gross	$ 10,174	$ 10,013
Residual value	142	164
Unearned income	(137)	(141)
Allowance for credit loss	(126)	(205)	$ (295)	$ (375)
Reported as:
Current	5,095	4,949
Noncurrent	4,958	4,882
Total, net	10,053	9,831
Lease Receivables
Financing Receivables [Line Items]
Gross	2,367	2,688
Residual value	142	164
Unearned income	(137)	(141)
Allowance for credit loss	(46)	(135)	(162)	(230)
Reported as:
Current	1,029	1,249
Noncurrent	1,297	1,327
Total, net	2,326	2,576
Loan Receivables
Financing Receivables [Line Items]
Gross	5,438	4,999
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(71)	(60)	(103)	(97)
Reported as:
Current	2,653	2,376
Noncurrent	2,714	2,563
Total, net	5,367	4,939
Financed Service Contracts
Financing Receivables [Line Items]
Gross	2,369	2,326
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(9)	(10)	$ (30)	$ (48)
Reported as:
Current	1,413	1,324
Noncurrent	947	992
Total, net	$ 2,360	$ 2,316

Notes, Loans And Financing Receivable, Net, Current And Non-current [Abstract]

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The estimate of the lease property's economic value at the end of the sales-type lease term excluding any amounts guaranteed by either the lessee or a third-party.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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