Consolidated Statement Of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 90,770	$ 114,216	$ 225,420	$ 223,781
Other comprehensive income (loss):
Foreign currency translation adjustment, net of tax	33,255	(91,430)	(39,090)	(281,737)
Unrealized gain on cash flow hedges, net of tax	20	0	78	0
Other comprehensive income (loss)	33,275	(91,430)	(39,012)	(281,737)
Total comprehensive income (loss)	$ 124,045	$ 22,786	$ 186,408	$ (57,956)