Concentration of Credit Risk Additional Information (Detail) (USD $) In Millions, unless otherwise specified		3 Months Ended	12 Months Ended	3 Months Ended
	Apr. 30, 2013	Apr. 30, 2013 Accounts Receivable	Jan. 31, 2013 Accounts Receivable	Apr. 30, 2013 Tech Data [Member]	Apr. 30, 2012 Tech Data [Member]
Concentration Risk [Line Items]
Unsecured revolving credit facility (in usd)	$ 400.0
Total sales to the distributors Tech Data Corporation and its global affiliates ("Tech Data") relative to Autodesk's consolidated net revenue				25.00%	22.00%
Percentage of gross accounts receivable accounted for by Tech Data		24.00%	23.00%