v2.4.0.6
Financing Receivables And Guarantees (Allowance For Credit Loss And Related Financing Receivables) (Detail) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Oct. 27, 2012
Oct. 29, 2011
Jul. 28, 2012
Jul. 31, 2010
Lease Receivables [Member]
        
Financing Receivable, Allowance for Credit Losses [Roll Forward]        
Financing Receivable, Allowance for Credit Losses $ 247     $ 237
Provisions (2) 2    
Foreign exchange and other 3 (6)    
Financing Receivable, Allowance for Credit Losses 248 233   237
Loan Receivables [Member]
        
Financing Receivable, Allowance for Credit Losses [Roll Forward]        
Financing Receivable, Allowance for Credit Losses 122     103
Provisions (10) 5    
Foreign exchange and other 2 (5)    
Financing Receivable, Allowance for Credit Losses 114 103   103
Capital Leases, Net Investment in Direct Financing Leases 1,816 1,468 1,796  
Financed Service Contracts And Other [Member]
        
Financing Receivable, Allowance for Credit Losses [Roll Forward]        
Financing Receivable, Allowance for Credit Losses 11     27
Provisions 1 2    
Foreign exchange and other 0 0    
Financing Receivable, Allowance for Credit Losses 12 29   27
Capital Leases, Net Investment in Direct Financing Leases 2,639 2,557 2,651  
Total Allowance [Member]
        
Financing Receivable, Allowance for Credit Losses [Roll Forward]        
Financing Receivable, Allowance for Credit Losses 380     367
Provisions (11) 9    
Foreign exchange and other 5 (11)    
Financing Receivable, Allowance for Credit Losses 374 365   367
Capital Leases, Net Investment in Direct Financing Leases 7,795 6,874    
Gross Receivables, Net of Unearned Income [Member] | Lease Receivables [Member]
        
Financing Receivable, Allowance for Credit Losses [Roll Forward]        
Capital Leases, Net Investment in Direct Financing Leases $ 3,340 $ 2,849 $ 3,179