Restructuring Reserve - Additional Information (Detail)	6 Months Ended	12 Months Ended
Jul. 31, 2011	Jan. 31, 2011 Person	Jan. 31, 2010 Person Entity	Jan. 31, 2009 Entity Person
Restructuring Cost and Reserve [Line Items]
Restructuring plan	During fiscal 2011, fiscal 2010 and fiscal 2009 Autodesk initiated restructuring plans (the “Fiscal 2011 Plan”, the “Fiscal 2010 Plan” and the “Fiscal 2009 Plan”) in order to further reduce operating costs.
Restructuring program, reduced the number of employees		200	430	700
Leased facilities that were consolidated			32	27

Information pertinent to an understanding of the specified type of restructuring cost, including the facts and circumstances leading to the expected activity, discussion of the level and quantity of personnel to be terminated, and the expected completion date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 146
-Paragraph 20
-Subparagraph 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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