Employee and Director Stock Plans - Stock-Based Compensation Expense - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
	Jan. 14, 2014	Jan. 31, 2015 Plan		Jan. 31, 2014		Jan. 31, 2013
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Number of Active Stock Plans		2
Number of Expired Plans		3
Number of additional share authorized (in shares)	11,400,000
Shares granted to shares issued (in shares)		2.11
Grants in period, net of forfeitures (in shares)		0	[1]
Shares available for future issuance (in shares)		55,000,000
Total compensation costs related to non-vested options		$ 0.6
Total compensation costs related to non-vested options, expected to be recognized over a weighted average period (in years)		2 months 12 days
Share based compensation expense, restricted stock units						0
Percentage of compensation that eligible employees can use to purchase common stock, maximum		15.00%
Percentage of fair market value eligible employees can purchase common stock, minimum		85.00%
Shares available for future issuance, increases on the first trading day of each fiscal year (In shares)		10,000,000
Shares available for future issuance, percentage of outstanding shares plus any shares repurchased by Autodesk (as a percent)		2.00%
Weighted average grant date fair value (in dollars per share)		$ 0	[2]	$ 0	[2]	$ 13.4	[2]
Employee Stock Plan 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares of common stock reserved for issuance (in shares)		32,600,000
Restricted stock award, net of forfeitures (in shares)		26,600,000
Shares forfeited (in shares)		6,000,000
Shares granted to shares issued (in shares)		1.79
Shares available for future issuance (in shares)		12,300,000
Vesting period		3 years
Outside directors stock plan 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares of common stock reserved for issuance (in shares)		2,600,000
Shares available for future issuance (in shares)		2,000,000
Outside directors stock plan 2012 | Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Vesting period		1 year
Outside directors stock plan 2012 | Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Vesting period		3 years
ESP Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares available for future issuance (in shares)		40,700,000
Shares issued under the ESP plan (in dollars per share)		2,100,000		2,900,000		2,900,000
Shares issued under the ESP Plan, average price (in dollars per share)		$ 33.91		$ 22.61		$ 21.79
Weighted average grant date fair value (in dollars per share)		$ 15.14		$ 11.80		$ 12.21
Employee Service Share Based Compensation recognized Compensation Costs On Nonvested Restricted Shares		23.9		22.9		34.0
Stock Options and Restricted Stock | Employee Stock Plan 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Grants in period, net of forfeitures (in shares)		22,100,000
Share based payment award options expiration term (in years)		10 years
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Granted (in dollars per share)		$ 54.17		$ 42.37		$ 33.32
Fair value of units vested in period		100.0		73.8		33.6
Restricted stock granted (in shares)		4,481,800
Number of awards granted but unreleased		7,801,300		6,515,600
Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Restricted stock granted (in shares)		4,000,000
Share based compensation expense, restricted stock units		118.9		74.9		70.5
Total compensation cost related to non-vested awards not yet recognized		245.0
Total compensation cost related to non-vested awards not yet recognized, weighted average period of recognition (in years)		1 year 9 months 29 days
Number of awards granted but unreleased		6,900,000
Restricted Stock Units (RSUs) | Outside directors stock plan 2012
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Grants in period, net of forfeitures (in shares)		600,000
Performance Stock Units (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Restricted stock granted (in shares)		500,000
Share based compensation expense, restricted stock units		17.5		8.7		8.1
Total compensation cost related to non-vested awards not yet recognized		2.5
Total compensation cost related to non-vested awards not yet recognized, weighted average period of recognition (in years)		9 months 14 days
Number of awards granted but unreleased		900,000
Performance Stock Units (PSUs) | Year One
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Vesting percentage (up to percentage)		33.33%
Performance Stock Units (PSUs) | Year Two
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Vesting percentage (up to percentage)		33.33%
Performance Stock Units (PSUs) | Year Three
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Vesting percentage (up to percentage)		33.33%
Goodwill acquired from other acquisitions | Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Share based compensation expense, restricted stock units						$ 16.6

[1] Autodesk did not grant stock options in the twelve months ended January 31, 2015.

[2] The weighted average grant date fair value per share of stock options granted is calculated, as of the stock option grant date, using the Black-Scholes Merton ("BSM") option pricing model. For the twelve months ended January 31, 2015 and 2014, Autodesk did not grant stock options.