Financing Receivables and Operating Leases (Schedule of Financing Receivables) (Details) - USD ($) $ in Millions	Jul. 28, 2018	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Financing Receivables [Line Items]
Allowance for credit loss	$ (205)	$ (295)	$ (375)	$ (382)
Reported as:
Current	4,949	4,856
Noncurrent	4,882	4,738
Lease Receivables
Financing Receivables [Line Items]
Gross	2,688	2,784
Residual value	164	173
Unearned income	(141)	(145)
Allowance for credit loss	(135)	(162)	(230)	(259)
Reported as:
Current	1,249	1,301
Noncurrent	1,327	1,349
Total, net	2,576	2,650
Loan Receivables
Financing Receivables [Line Items]
Gross	4,999	4,560
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(60)	(103)	(97)	(87)
Reported as:
Current	2,376	2,104
Noncurrent	2,563	2,353
Total, net	4,939	4,457
Financed Service Contracts
Financing Receivables [Line Items]
Gross	2,326	2,517
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(10)	(30)	$ (48)	$ (36)
Reported as:
Current	1,324	1,451
Noncurrent	992	1,036
Total, net	2,316	2,487
Total
Financing Receivables [Line Items]
Gross	10,013	9,861
Residual value	164	173
Unearned income	(141)	(145)
Allowance for credit loss	(205)	(295)
Reported as:
Current	4,949	4,856
Noncurrent	4,882	4,738
Total, net	$ 9,831	$ 9,594

Financing Receivables [Line Items]

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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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A valuation allowance for financing receivables that are expected to be uncollectible.

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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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