Financing Receivables and Operating Leases (Schedule of Financing Receivables) (Details) - USD ($) $ in Millions	Oct. 27, 2018	Jul. 28, 2018	Oct. 28, 2017	Jul. 29, 2017
Financing Receivables [Line Items]
Allowance for credit loss	$ (199)	$ (205)	$ (289)	$ (295)
Current	4,851	4,949
Lease Receivables
Financing Receivables [Line Items]
Gross	2,511	2,688
Residual value	159	164
Unearned income	(140)	(141)
Allowance for credit loss	(131)	(135)
Total, net	2,399	2,576
Current	1,143	1,249
Noncurrent	1,256	1,327
Loan Receivables
Financing Receivables [Line Items]
Gross	4,924	4,999
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(60)	(60)
Total, net	4,864	4,939
Current	2,422	2,376
Noncurrent	2,442	2,563
Financed Service Contracts
Financing Receivables [Line Items]
Gross	2,240	2,326
Residual value	0	0
Unearned income	0	0
Allowance for credit loss	(8)	(10)
Total, net	2,232	2,316
Current	1,286	1,324
Noncurrent	946	992
Total
Financing Receivables [Line Items]
Gross	9,675	10,013
Residual value	159	164
Unearned income	(140)	(141)
Allowance for credit loss	(199)	(205)
Total, net	9,495	9,831
Current	4,851	4,949
Noncurrent	$ 4,644	$ 4,882

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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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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 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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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) more than one year from the balance sheet date. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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