Revenue Recognition - Contract Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Disaggregation of Revenue [Line Items]
Net revenue	$ 1,125.8	$ 952.4	$ 3,174.8	$ 2,751.2
Design
Disaggregation of Revenue [Line Items]
Net revenue	994.4	847.7	2,823.5	2,466.8
Make
Disaggregation of Revenue [Line Items]
Net revenue	93.9	76.5	265.0	214.9
Other
Disaggregation of Revenue [Line Items]
Net revenue	37.5	28.2	86.3	69.5
Indirect
Disaggregation of Revenue [Line Items]
Net revenue	729.3	656.2	2,092.8	1,918.9
Direct
Disaggregation of Revenue [Line Items]
Net revenue	396.5	296.2	1,082.0	832.3
Americas
Disaggregation of Revenue [Line Items]
Net revenue	461.9	392.9	1,276.4	1,126.6
U.S.
Disaggregation of Revenue [Line Items]
Net revenue	383.2	328.5	1,054.5	938.6
Other Americas
Disaggregation of Revenue [Line Items]
Net revenue	78.7	64.4	221.9	188.0
Europe, Middle East, and Africa
Disaggregation of Revenue [Line Items]
Net revenue	433.2	364.3	1,225.9	1,063.8
Asia Pacific
Disaggregation of Revenue [Line Items]
Net revenue	230.7	195.2	672.5	560.8
Architecture, Engineering and Construction
Disaggregation of Revenue [Line Items]
Net revenue	511.1	419.4	1,432.4	1,199.1
AutoCAD and AutoCAD LT
Disaggregation of Revenue [Line Items]
Net revenue	318.4	278.8	907.9	812.9
Manufacturing
Disaggregation of Revenue [Line Items]
Net revenue	225.0	194.1	630.0	562.5
Media and Entertainment
Disaggregation of Revenue [Line Items]
Net revenue	63.0	54.0	176.5	159.9
Other
Disaggregation of Revenue [Line Items]
Net revenue	$ 8.3	$ 6.1	$ 28.0	$ 16.8