v2.4.0.6

Taxes - Additional Information (Detail) (USD $) | 12 Months Ended | 6 Months Ended | 12 Months Ended |  | 12 Months Ended |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 31, 2012 | Oct. 31, 2011 | Oct. 31, 2010 | Oct. 31, 2010 Increase Net | Oct. 31, 2012 Internal Revenue Service (IRS) Fiscal Years 2010 and 2011 | Apr. 30, 2011 Internal Revenue Service (IRS) Fiscal Years 2006 through 2009 | Oct. 31, 2012 Taiwan Fiscal Year 2008 | Oct. 31, 2012 Hungary Fiscal Year 2006 Through 2008 | Oct. 31, 2012 Hungary Fiscal Years 2009 And 2010 | Oct. 31, 2012 Hungary Fiscal Years 2009 And 2010 Cash Payment Obligations | Oct. 31, 2012 Hungary Fiscal Years 2009 And 2010 Cash payment | Jul. 31, 2012 Hungary Fiscal Year 2006 Through 2010 | Apr. 30, 2012 Hungary Fiscal Year 2006 Through 2010 | Jan. 31, 2011 Synplicity, Inc. | Oct. 31, 2010 Avant! Corporation
Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase in valuation allowance | $ 12,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized deferred tax assets | 48,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Undistributed foreign earnings | 615,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tax on deferred undistributed foreign earnings | 135,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Decrease in gross unrecognized tax benefits | 68,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross unrecognized tax benefits | 109,680,000 | 177,893,000 | 213,923,000 |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized tax benefits affecting effective tax rate | 75,300,000 | 177,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |
The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations | (5,800,000) | 2,800,000 | 3,400,000 |  |  |  |  |  |  |  |  |  |  |  |
The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations | 600,000 | 7,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated potential decrease in underlying unrecognized tax benefits, minimum | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated potential decrease in underlying unrecognized tax benefits, maximum | 16,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities | 80,137,000 | 1,258,000 |  |  | 24,700,000 | 35,900,000 | 16,500,000 |  |  |  |  | 24,200,000 | 27,000,000 | 4,000,000 | 67,800,000
Tax impact from tax settlements |  |  |  |  | 15,900,000 | 32,800,000 | 14,700,000 |  | 6,300,000 |  |  |  |  |  | 94,300,000
Release of valuation allowance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 21,600,000
Tax adjustments settlements and unusual provisions |  |  | 72,300,000 | 55,400,000 |  |  |  |  |  |  |  |  |  |  |
Decrease in deferred tax assets due to utilization of foreign tax credit carryover net of reversal of valuation allowance |  |  | 25,200,000 |  |  |  |  |  |  |  |  |  |  |  |
Cash payments as a result of settlement |  |  |  |  |  |  |  | $ 5,100,000 |  | $ 3,200,000 | $ 10,900,000 |  |  |  |

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- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -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 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 + Details
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- Definition Reflects the effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 48 -Paragraph 10A, 10B, 10C -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 FASB Interpretation (FIN) -Number 48 -Paragraph 10 -Subparagraph 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. + Details
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- Definition The portion of the deferred tax asset arising from a tax credit carryforward for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 48 -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 -Glossary Valuation Allowance -URI http://asc.fasb.org/extlink&oid=6528051 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43 -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 17 -Subparagraph e -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. + Details
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