Penalties imposed on the amount of additional tax.

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 6.I)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The tax year(s) being audited in connection with the income tax examination.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)(2)

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- Definition

The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

+ 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 (d)

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The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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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 10

-Subparagraph b

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-Publisher FASB

-Name FASB Interpretation (FIN)

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-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.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

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Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Oct. 31, 2011
Taxes [Line Items]
Statutory federal income tax rate		35.00%
Tax impact of final settlement with IRS			$ 32.8
Estimated potential decrease in underlying unrecognized tax benefits, minimum	0
Estimated potential decrease in underlying unrecognized tax benefits, maximum	178
Decrease in unrecognized tax benefits resulting from settlement with the IRS			35.9
Income tax examination years			IRS for its audits of fiscal years 2006 through 2009
Penalties imposed on the amount of additional tax	50.00%
Synplicity, Inc. [Member]
Taxes [Line Items]
Decrease in unrecognized tax benefits resulting from settlement with the IRS		4.0