Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2017	Apr. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (9,207)	$ 38,759
Other comprehensive income, before tax and net of reclassification adjustments:
Foreign currency translation and other gains (losses)	14,024	10,256
Unrealized gains on marketable securities and strategic investments	71,330	11,084
Other comprehensive income, before tax	85,354	21,340
Tax effect	0	0
Other comprehensive income, net of tax	85,354	21,340
Comprehensive income	$ 76,147	$ 60,099