Employee and Director Stock Plans - Options Outstanding and Exercisable (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Jan. 31, 2014		Jan. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Vested and Exercisable, Number of Shares	4.0
Options Vested and Exercisable, Weighted average contractual life (in years)	3 years 11 months 26 days
Options Vested and Exercisable, Weighted average exercise price	$ 30.98
Options Vested and Exercisable, Aggregate intrinsic value	$ 80.3	[1]
Options Outstanding, Number of Shares	5.9		19.0
Options Outstanding, Weighted average contractual life (in years)	4 years 9 months 7 days
Options Outstanding, Weighted average exercise price	$ 33.54		$ 32.69
Options Outstanding, Aggregate Intrinsic Value	$ 105.3	[1]
Closing stock price (in dollars per share)	$ 51.25
$2.28 - $29.49
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of per-share exercise prices, Lower Limit	$ 2.28
Range of per-share exercise prices, Upper Limit	$ 29.49
Options Vested and Exercisable, Number of Shares	1.8
Options Vested and Exercisable, Weighted average exercise price	$ 22.73
Options Outstanding, Number of Shares	2.1
Options Outstanding, Weighted average exercise price	$ 23.51
$29.50 - $38.08
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of per-share exercise prices, Lower Limit	$ 29.5
Range of per-share exercise prices, Upper Limit	$ 38.08
Options Vested and Exercisable, Number of Shares	0.9
Options Vested and Exercisable, Weighted average exercise price	$ 32.75
Options Outstanding, Number of Shares	1.2
Options Outstanding, Weighted average exercise price	$ 32.46
$38.55 - $38.55
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of per-share exercise prices, Lower Limit	$ 38.55
Range of per-share exercise prices, Upper Limit	$ 38.55
Options Vested and Exercisable, Number of Shares	0.1
Options Vested and Exercisable, Weighted average exercise price	$ 38.55
Options Outstanding, Number of Shares	0.1
Options Outstanding, Weighted average exercise price	$ 38.55
$41.62 - $41.62
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of per-share exercise prices, Lower Limit	$ 41.62
Range of per-share exercise prices, Upper Limit	$ 41.62
Options Vested and Exercisable, Number of Shares	0.9
Options Vested and Exercisable, Weighted average exercise price	$ 41.62
Options Outstanding, Number of Shares	2.0
Options Outstanding, Weighted average exercise price	$ 41.62
$42.39 - $43.81
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of per-share exercise prices, Lower Limit	$ 42.39
Range of per-share exercise prices, Upper Limit	$ 43.81
Options Vested and Exercisable, Number of Shares	0.3
Options Vested and Exercisable, Weighted average exercise price	$ 43.80
Options Outstanding, Number of Shares	0.5
Options Outstanding, Weighted average exercise price	$ 43.79

[1] Represents the total pre-tax intrinsic value, based on Autodesk’s closing stock price of $51.25 per share as of January 31, 2014, which would have been received by the option holders had all option holders exercised their options as of that date.