Share-Based Compensation Expense (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Jul. 31, 2011	Oct. 31, 2010
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 0.01
Range of Exercise Price, Upper	$ 267.52
Weighted Average Exercise Price, Options Outstanding	$ 38.49	$ 40.96
Range of Exercise Price Range One [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 0.01
Range of Exercise Price, Upper	$ 16.52
Range of Exercise Price Range One [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	635
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	5.41
Weighted Average Exercise Price, Options Outstanding	$ 11.37
Aggregate Intrinsic Value	$ 2,852
Range of Exercise Price Range One [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	511
Weighted Average, Vested Options Remaining Contractual Life (Years)	4.82
Weighted Average Exercise Price, Vested Options	$ 11.68
Aggregate Intrinsic Value	2,188
Range of Exercise Price Range Two [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 16.53
Range of Exercise Price, Upper	$ 17.43
Range of Exercise Price Range Two [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	351
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	4.12
Weighted Average Exercise Price, Options Outstanding	$ 17.20
Aggregate Intrinsic Value	0
Range of Exercise Price Range Two [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	337
Weighted Average, Vested Options Remaining Contractual Life (Years)	3.99
Weighted Average Exercise Price, Vested Options	$ 17.20
Aggregate Intrinsic Value	0
Range of Exercise Price Range Three [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 17.44
Range of Exercise Price, Upper	$ 22.96
Range of Exercise Price Range Three [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	339
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	3.75
Weighted Average Exercise Price, Options Outstanding	$ 21.80
Aggregate Intrinsic Value	0
Range of Exercise Price Range Three [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	326
Weighted Average, Vested Options Remaining Contractual Life (Years)	3.61
Weighted Average Exercise Price, Vested Options	$ 21.85
Aggregate Intrinsic Value	0
Range of Exercise Price Range Four [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 22.97
Range of Exercise Price, Upper	$ 31.71
Range of Exercise Price Range Four [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	1,253
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	3.36
Weighted Average Exercise Price, Options Outstanding	$ 29.42
Aggregate Intrinsic Value	0
Range of Exercise Price Range Four [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	1,226
Weighted Average, Vested Options Remaining Contractual Life (Years)	3.29
Weighted Average Exercise Price, Vested Options	$ 29.45
Aggregate Intrinsic Value	0
Range of Exercise Price Range Five [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 31.72
Range of Exercise Price, Upper	$ 46.90
Range of Exercise Price Range Five [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	755
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	4.67
Weighted Average Exercise Price, Options Outstanding	$ 39.25
Aggregate Intrinsic Value	0
Range of Exercise Price Range Five [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	712
Weighted Average, Vested Options Remaining Contractual Life (Years)	4.57
Weighted Average Exercise Price, Vested Options	$ 39.40
Aggregate Intrinsic Value	0
Range of Exercise Price Range Six [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 46.91
Range of Exercise Price, Upper	$ 73.78
Range of Exercise Price Range Six [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	399
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	1.37
Weighted Average Exercise Price, Options Outstanding	$ 59.14
Aggregate Intrinsic Value	0
Range of Exercise Price Range Six [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	399
Weighted Average, Vested Options Remaining Contractual Life (Years)	1.37
Weighted Average Exercise Price, Vested Options	$ 59.14
Aggregate Intrinsic Value	0
Range of Exercise Price Range Seven [Member]
Summarizes information with respect to stock options outstanding
Range of Exercise Price, Lower	$ 73.79
Range of Exercise Price, Upper	$ 267.52
Range of Exercise Price Range Seven [Member] \| Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	423
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	0.22
Weighted Average Exercise Price, Options Outstanding	$ 116.21
Aggregate Intrinsic Value	0
Range of Exercise Price Range Seven [Member] \| Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	423
Weighted Average, Vested Options Remaining Contractual Life (Years)	0.22
Weighted Average Exercise Price, Vested Options	$ 116.21
Aggregate Intrinsic Value	0
Options Outstanding [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Options Outstanding	4,155
Weighted Average, Outstanding Options Remaining Contractual Life (Years)	3.50
Weighted Average Exercise Price, Options Outstanding	$ 38.49
Aggregate Intrinsic Value	2,852
Vested Options [Member]
Summarizes information with respect to stock options outstanding
Number of Shares, Vested Options	3,934
Weighted Average, Vested Options Remaining Contractual Life (Years)	3.28
Weighted Average Exercise Price, Vested Options	$ 39.61
Aggregate Intrinsic Value	$ 2,188

Summarizes information with respect to stock options outstanding.

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- Definition

The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

As of the balance sheet date, the total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph d(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average remaining life of the exercisable stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(c)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a, b)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted-average period remaining as of the balance sheet date until option expiration pertaining to the outstanding stock options for all option plans in the customized range of exercise prices, which may be expressed in a variety of ways (for example, years, months).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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