Other Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Other Income and Expenses [Abstract]
Foreign currency gain (loss)	$ 2,275	$ (708)	$ (2,103)
(Amortization) accretion on investments	(3,082)	3,001	2,492
Interest income, net	15,859	25,185	15,388
Miscellaneous income	1,147	0	0
Other income, net	$ 16,199	$ 27,478	$ 15,777