Stock-based Compensation Expense Summary of Restricted Stock Award and Restricted Stock Unit Activity (Details) - $ / shares		9 Months Ended
		Oct. 31, 2015	Oct. 31, 2014	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Restricted Stock Units (RSUs) and Performance Shares
Unvested Restricted Stock Units
Unvested restricted stock units at January 31, 2015 (shares)		7,801,300
Granted (shares)		3,268,800
Vested (shares)		(2,949,100)
Canceled/Forfeited (shares)		(364,600)
Unvested restricted stock units at July 31, 2015 (shares)		7,791,000
Weighted average grant date fair value per share
Unvested restricted stock units at January 31, 2015 (usd per share)		$ 48.46
Granted (in usd per share)		50.42	$ 52.89
Vested (in usd per share)		44.61
Canceled/Forfeited (in usd per share)		49.86
Unvested restricted stock units at July 31, 2015 (usd per share)		$ 50.60
Performance shares units payout				113.80%	65.80%	92.30%
Restricted Stock Units (RSUs)
Unvested Restricted Stock Units
Granted (shares)		2,800,000
Unvested restricted stock units at July 31, 2015 (shares)		7,000,000
Performance Stock Unit
Unvested Restricted Stock Units
Granted (shares)		400,000
Performance adjustment (shares)	[1]	34,600
Unvested restricted stock units at July 31, 2015 (shares)		800,000
Weighted average grant date fair value per share
Performance adjustment (in usd per share)	[1]	$ 54.92

[1] Based on Autodesk's financial results for fiscal 2015, 2014 and 2013 performance period. The performance stock units were earned at 113.8%, 65.8%, and 92.3% of the target award, respectively.