Debt - Schedule of Debt Instruments (Details) - USD ($) $ in Millions	Jul. 31, 2017	Apr. 30, 2017	Oct. 31, 2016
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations	$ 4,255		$ 3,997
Financial Services Operations
Debt Instrument [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	1,796		1,808
Long-term Debt and Capital Lease Obligations, Current	851		836
Long-term Debt and Capital Lease Obligations	945		972
Financial Services Operations \| Secured Debt [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 6	6
Long-term Debt	822		753
Financial Services Operations \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		2	3
Long-term Debt	774		861
Financial Services Operations \| Commercial Paper [Member]
Debt Instrument [Line Items]
Long-term Debt	100		96
Financial Services Operations \| Borrowings Secured By Operating and Finance Leases [Member]
Debt Instrument [Line Items]
Long-term Debt	100		98
Manufacturing Operations [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		4
Long-term Debt and Capital Lease Obligations, Including Current Maturities	3,424		3,096
Long-term Debt and Capital Lease Obligations, Current	114		71
Long-term Debt and Capital Lease Obligations	3,310		3,025
Manufacturing Operations [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		11	7
Debt Instrument, Unamortized Discount		9	14
Long-term Debt	1,001		1,009
Manufacturing Operations [Member] \| Notes Payable to Banks [Member] \| Eight Point Two Five Percent Senior Notes [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		14	12
Debt Instrument, Unamortized Discount		$ 14	15
Debt Instrument, Interest Rate, Stated Percentage		8.25%
Long-term Debt	$ 1,422		1,173
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Five Zero Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 1	1
Debt Instrument, Unamortized Discount		$ 6	10
Debt Instrument, Interest Rate, Stated Percentage	4.50%	4.50%
Long-term Debt	$ 193		189
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 3	4
Debt Instrument, Unamortized Discount		$ 17	24
Debt Instrument, Interest Rate, Stated Percentage	4.75%	4.75%
Long-term Debt	$ 391		383
Manufacturing Operations [Member] \| Financing Arrangements and Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 36		42
Manufacturing Operations [Member] \| Tax Exempt Bond [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 5	5
Debt Instrument, Interest Rate, Stated Percentage	6.50%	6.50%
Long-term Debt	$ 220		220
Manufacturing Operations [Member] \| Financed lease obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	127		52
Manufacturing Operations [Member] \| Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 34		$ 28

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Publisher FASB
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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 leases due within one year or 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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