Financing Receivables - Schedule of Financing Receivables (Details) - USD ($) $ in Millions	Oct. 26, 2019	Jul. 27, 2019	Oct. 27, 2018	Jul. 28, 2018
Financing Receivables [Line Items]
Gross	$ 9,986	$ 10,174
Residual value	138
Residual value		142
Unearned income	(134)	(137)
Allowance for credit loss	(133)	(126)	$ (199)	$ (205)
Total, net	9,857	10,053
Current	5,026	5,095
Noncurrent	4,831	4,958
Lease Receivables
Financing Receivables [Line Items]
Gross	2,218	2,367
Residual value	138
Residual value		142
Unearned income	(134)	(137)
Allowance for credit loss	(43)	(46)
Total, net	2,179	2,326
Current	976	1,029
Noncurrent	1,203	1,297
Loan Receivables
Financing Receivables [Line Items]
Gross	5,335	5,438
Unearned income	0	0
Allowance for credit loss	(81)	(71)
Total, net	5,254	5,367
Current	2,575	2,653
Noncurrent	2,679	2,714
Financed Service Contracts
Financing Receivables [Line Items]
Gross	2,433	2,369
Unearned income	0	0
Allowance for credit loss	(9)	(9)
Total, net	2,424	2,360
Current	1,475	1,413
Noncurrent	$ 949	$ 947

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Financing Receivables [Line Items]

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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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount, before allowance for credit loss, of financing receivable, classified as noncurrent.

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Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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Present value expected to be derived from underlying asset following end of lease term not guaranteed by lessee or other third party unrelated to lessor.

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