Consolidated Statement Of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 114,216	$ 37,268	$ 223,781	$ 115,381
Other comprehensive (loss) income:
Foreign currency translation adjustment	(91,430)	(54,159)	(281,737)	174,942
Total comprehensive income (loss)	$ 22,786	$ (16,891)	$ (57,956)	$ 290,323