Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Income Tax Disclosure [Abstract]
Income before provision for income taxes	$ 228,931	$ 29,175
Provision for income taxes	$ 1,400	$ 2,100
Effective tax rate	0.60%	7.20%