Significant Accounting Policies (Details)	9 Months Ended
Jul. 31, 2011	Jul. 31, 2010
Additional Significant Accounting Policies (Textuals) [Abstract]
Interest on convertible notes	4.00%	4.00%
Significant Accounting Policies (Textuals) [Abstract]
Estimated useful lives capitalized and amortized straight -line minimum	2
Estimated useful lives capitalized and amortized straight -line Maximum	5
Minimum Expected economic lives of Finite-lived intangible assets	0.75
Maximum Expected economic lives of Finite-lived intangible assets	7
Expected number of years Spares usage cost is expensed	4 years
One-time employee termination benefits related to service period	more than 60 days
Four Percent Convertible Senior Notes Due 2015 [Member]
Additional Significant Accounting Policies (Textuals) [Abstract]
Interest on convertible notes	4.00%

Additional Significant Accounting Policies.

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One-time employee termination benefits related to service period.

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Other Long Term Asset Useful Life.

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Significant Accounting Policies.

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The maximum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 35
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15217-109273

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15300-109273

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15211-109273

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The minimum useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ References

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The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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The minimum useful life of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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