Consolidated Statement Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 47,459	$ 46,394	$ 78,113	$ 79,767
Other comprehensive income (loss):
Foreign currency translation adjustment	195,438	(76,990)	229,101	19,002
Total comprehensive income (loss)	$ 242,897	$ (30,596)	$ 307,214	$ 98,769