Financing Receivables and Guarantees (Schedule of Internal Credit Risk Rating for Each Portfolio Segment and Class) (Details) (USD $) In Millions	Apr. 30, 2011
Internal Credit Risk Rating 1 to 4	$ 3,173
Internal Credit Risk Rating 5 to 6	2,876
Internal Credit Risk Rating 7 and higher	174
Total	6,223
Residual value	293
Gross receivables, net of unearned income	6,516
Lease Receivables [Member]
Gross receivables, net of unearned income	2,648
Lease Receivables [Member] | Established Markets [Member]
Internal Credit Risk Rating 1 to 4	1,054
Internal Credit Risk Rating 5 to 6	1,144
Internal Credit Risk Rating 7 and higher	26
Total	2,224
Residual value	288
Gross receivables, net of unearned income	2,512
Lease Receivables [Member] | Growth Markets [Member]
Internal Credit Risk Rating 1 to 4	20
Internal Credit Risk Rating 5 to 6	91
Internal Credit Risk Rating 7 and higher	20
Total	131
Residual value	5
Gross receivables, net of unearned income	136
Financed Service Contracts & Other [Member]
Gross receivables, net of unearned income	2,495
Financed Service Contracts & Other [Member] | Established Markets [Member]
Internal Credit Risk Rating 1 to 4	1,549
Internal Credit Risk Rating 5 to 6	892
Internal Credit Risk Rating 7 and higher	52
Total	2,493
Residual value
Gross receivables, net of unearned income	2,493
Financed Service Contracts & Other [Member] | Growth Markets [Member]
Internal Credit Risk Rating 1 to 4
Internal Credit Risk Rating 5 to 6	2
Internal Credit Risk Rating 7 and higher
Total	2
Residual value
Gross receivables, net of unearned income	2
Loan Receivables [Member]
Gross receivables, net of unearned income	1,373
Loan Receivables [Member] | Established Markets [Member]
Internal Credit Risk Rating 1 to 4	216
Internal Credit Risk Rating 5 to 6	163
Internal Credit Risk Rating 7 and higher	1
Total	380
Residual value
Gross receivables, net of unearned income	380
Loan Receivables [Member] | Growth Markets [Member]
Internal Credit Risk Rating 1 to 4	334
Internal Credit Risk Rating 5 to 6	584
Internal Credit Risk Rating 7 and higher	75
Total	993
Residual value
Gross receivables, net of unearned income	993
Established Markets [Member]
Internal Credit Risk Rating 1 to 4	2,819
Internal Credit Risk Rating 5 to 6	2,199
Internal Credit Risk Rating 7 and higher	79
Total	5,097
Residual value	288
Gross receivables, net of unearned income	5,385
Growth Markets [Member]
Internal Credit Risk Rating 1 to 4	354
Internal Credit Risk Rating 5 to 6	677
Internal Credit Risk Rating 7 and higher	95
Total	1,126
Residual value	5
Gross receivables, net of unearned income	$ 1,131