Consolidated Statement Of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 55,400	$ 33,699
Other comprehensive loss:
Foreign currency translation adjustment, net of tax	(40,523)	(88,252)
Unrealized loss on cash flow hedges, net of tax	(211)	0
Other comprehensive income (loss), net of tax	(40,734)	(88,252)
Total comprehensive income (loss)	$ 14,666	$ (54,553)