Other Income (Expense), Net Other Income (Expense), Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Other Income and Expenses [Abstract]
Interest income	$ 2,777	$ 1,870	$ 1,723
Foreign currency exchange gain (loss)	729	199	(1,152)
Other, net	(1,257)	(457)	(1,348)
Other income (expense), net	$ 2,249	$ 1,612	$ (777)