Consolidated Statement Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 36,506	$ 41,900	$ 116,273	$ 169,589
Other comprehensive loss:
Foreign currency translation adjustment	(55,771)	(4,815)	(36,769)	(22,228)
Total comprehensive (loss) income	$ (19,265)	$ 37,085	$ 79,504	$ 147,361