Short-Term and Long-Term Debt - Outstanding Convertible Notes Payable Debt Components (Details) $ in Thousands	9 Months Ended
Jul. 31, 2018 USD ($)
3.75% Convertible Senior Notes due October 15, 2018 (Original)
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)	3.75%
3.75% Convertible Senior Notes due October 15, 2018 (New)
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)	3.75%
4.0% Convertible Senior Notes due December 15, 2020
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)	4.00%
Convertible notes payable \| 3.75% Convertible Senior Notes due October 15, 2018 (Original)
Debt Instrument [Line Items]
Principal Balance	$ 61,270
Unamortized Debt Discount	0
Deferred Debt Issuance Costs	(36)
Net Carrying Value	61,234
Equity component, Net carrying value	$ 0
Interest rate on convertible notes (as a percent)	3.75%
Convertible notes payable \| 3.75% Convertible Senior Notes due October 15, 2018 (New)
Debt Instrument [Line Items]
Principal Balance	$ 288,730
Unamortized Debt Discount	(125)
Deferred Debt Issuance Costs	(170)
Net Carrying Value	288,435
Equity component, Net carrying value	$ 0
Interest rate on convertible notes (as a percent)	3.75%
Convertible notes payable \| 4.0% Convertible Senior Notes due December 15, 2020
Debt Instrument [Line Items]
Principal Balance	$ 207,809
Unamortized Debt Discount	(7,437)
Deferred Debt Issuance Costs	(730)
Net Carrying Value	199,642
Equity component, Net carrying value	$ 43,131
Accretion rate of principal amount	1.85%
Interest rate on convertible notes (as a percent)	4.00%

Accretion Rate of Principal Amount

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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

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Amount, after accumulated amortization, of debt discount.

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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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