Income Taxes (Details 2)	12 Months Ended
Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2009
Income tax rate reconciliation:
Provision at statutory rate	35.00%	35.00%	35.00%
State taxes	0.27%	(0.07%)	(0.02%)
Foreign taxes	2.32%	(4.56%)	0.05%
Research and development credit	11.03%	2.54%	0.60%
Goodwill impairment	0.00%	0.00%	(27.38%)
Non-deductible compensation and other	(3.96%)	(1.43%)	(1.42%)
Valuation allowance	(48.74%)	(32.07%)	(6.60%)
Effective income tax rate	(4.08%)	(0.59%)	0.23%

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost and Other

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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-Publisher FASB

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

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-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to nondeductible impairment losses under enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by research tax credits generated or utilized under enacted tax laws during the period.

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