LONG-TERM DEBT (Details) - USD ($) $ in Millions	Jul. 31, 2018	Oct. 31, 2017
Debt Instrument
Amortized principal	$ 1,791	$ 1,790
Interest rate swap	8	11
Long-term debt	1,799	1,801
Senior Notes 2020
Debt Instrument
Amortized principal	500	499
Interest rate swap	8	11
Long-term debt	508	510
Senior Notes 2022
Debt Instrument
Amortized principal	398	398
Interest rate swap	0	0
Long-term debt	398	398
Senior Notes 2023
Debt Instrument
Amortized principal	596	596
Interest rate swap	0	0
Long-term debt	596	596
Senior Notes 2026
Debt Instrument
Amortized principal	297	297
Interest rate swap	0	0
Long-term debt	$ 297	$ 297

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Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective interest rate fair value hedge that is amortized upon discontinuation of the interest rate fair value hedge.

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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