Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Earnings Per Share Calculation - Antidilutive Securities Excluded (Details) - shares shares in Thousands	3 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Oct. 31, 2018	Aug. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total excluded due to anti-dilutive effect (in shares)	401	16,341
3.75% Convertible Senior Notes due October 15, 2018 (Original)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate on convertible notes (as a percent)			3.75%
3.75% Convertible Senior Notes due October 15, 2018 (New)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate on convertible notes (as a percent)			3.75%	3.75%
4.0% Convertible Senior Notes due December 15, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate on convertible notes (as a percent)			4.00%
Shares underlying stock options and restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total excluded due to anti-dilutive effect (in shares)	401	3,414
Convertible Senior Notes \| 3.75% Convertible Senior Notes due October 15, 2018 (Original)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total excluded due to anti-dilutive effect (in shares)	0	3,038
Convertible Senior Notes \| 3.75% Convertible Senior Notes due October 15, 2018 (New)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total excluded due to anti-dilutive effect (in shares)	0	691
Convertible Senior Notes \| 4.0% Convertible Senior Notes due December 15, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total excluded due to anti-dilutive effect (in shares)	0	9,198