Contractual interest rate for funds borrowed, under the debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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Debt - Schedule of Debt Instruments (Details) (USD $) In Millions, unless otherwise specified	Oct. 31, 2014	Oct. 31, 2013	Apr. 30, 2014	Oct. 31, 2012
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ 82
Long-term Debt	5,224us-gaap_LongTermDebt
Long-term Debt and Capital Lease Obligations	3,929	3,922
Convertible Subordinated Debt [Member] \| Four Point Five Zero Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount		1
Convertible Subordinated Debt [Member] \| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount			1
Financial Services Operations [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	0
Long-term Debt	2,266
Long-term Debt and Capital Lease Obligations, Including Current Maturities	2,266	1,866
Long-term Debt and Capital Lease Obligations, Current	1,195	505
Long-term Debt and Capital Lease Obligations	1,071	1,361
Financial Services Operations [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	914	778
Financial Services Operations [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Long-term Debt	1,242	1,018
Financial Services Operations [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Long-term Debt	74	21
Financial Services Operations [Member] \| Borrowings Secured By Operating and Finance Leases [Member]
Debt Instrument [Line Items]
Long-term Debt	36	49
Manufacturing Operations [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	82
Long-term Debt	2,958
Long-term Debt and Capital Lease Obligations, Including Current Maturities	2,958	3,219
Long-term Debt and Capital Lease Obligations, Current	100	658
Long-term Debt and Capital Lease Obligations	2,858	2,561
Manufacturing Operations [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	3	4
Long-term Debt	694	693
Manufacturing Operations [Member] \| Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		8.25%
Manufacturing Operations [Member] \| Notes Payable to Banks [Member] \| Eight Point Two Five Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	20	22
Debt Instrument, Interest Rate, Stated Percentage	8.25%
Long-term Debt	1,180	1,178
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Three Point Zero Percent Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	0	26
Debt Instrument, Interest Rate, Stated Percentage	3.00%
Long-term Debt	0	544
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Five Zero Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	19	23
Debt Instrument, Interest Rate, Stated Percentage	4.50%	4.50%
Long-term Debt	181	177
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	40
Debt Instrument, Interest Rate, Stated Percentage	4.75%		4.75%
Long-term Debt	371	0
Manufacturing Operations [Member] \| Debt Of Majority Owned Dealerships [Member]
Debt Instrument [Line Items]
Long-term Debt	30	48
Manufacturing Operations [Member] \| Financing Arrangements and Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	54	77
Manufacturing Operations [Member] \| Tax Exempt Bond [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%			6.50%
Long-term Debt	225	225
Manufacturing Operations [Member] \| Promissory Note [Member]
Debt Instrument [Line Items]
Long-term Debt	10	20
Manufacturing Operations [Member] \| Financed lease obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	184	218
Manufacturing Operations [Member] \| Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 29	$ 39