Consolidated Statement Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 46,394	$ 76,412	$ 79,767	$ 127,689
Other comprehensive (loss) income:
Foreign currency translation adjustment	(76,990)	(25,893)	19,002	(17,413)
Total comprehensive (loss) income	$ (30,596)	$ 50,519	$ 98,769	$ 110,276