Common Stock, Average Market Price

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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-Publisher FASB
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Earnings Per Share Calculation - Antidilutive Securities Excluded (Details) - $ / shares shares in Thousands	3 Months Ended		6 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Oct. 31, 2017	Jul. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock average market price (in dollars per share)	$ 24.76		$ 24.76
Total excluded due to anti-dilutive effect (in shares)	12,540	9,923	16,404	27,695
0.875% Convertible Senior Notes due June 15, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate on convertible notes (as a percent)					0.875%	0.875%
Dilutive conversion spread (in shares)	0	4,857	0	5,210
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%
Dilutive conversion spread (in shares)	0	17,356	0	0
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%
Shares of underlying convertible senior notes due (in shares)			14,300
Dilutive conversion spread (in shares)	2,653	0	0	0
Initial conversion price per share equivalent (in dollars per share)	$ 20.17		$ 20.17
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%		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)	304	725	2,496	1,141
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)	3,038	0	3,038	17,356
Convertible Senior Notes \| 3.75% Convertible Senior Notes due October 15, 2018 (New)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive conversion spread (in shares)	2,700
Total excluded due to anti-dilutive effect (in shares)	0	0	1,672	0
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)	9,198	9,198	9,198	9,198