Leases - Other information (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Leases [Abstract]
Weighted average remaining lease term	5 years 8 months 12 days
Weighted average discount rate	8.30%
Cash paid for amounts included in the measurement of operating lease liabilities	$ 108.9	$ 100.8
Right-of-use assets obtained in exchange for lease obligations	$ 56.6	$ 27.0