Other Income (Expense), Net Other Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Other Income and Expenses [Abstract]
Interest income	$ 6,834	$ 1,871
Interest expense	(6,667)	(1,498)
Foreign currency transactions gains (losses)	(1,981)	(2,134)
Other income (expense)	(2)	762
Total other income (expense), net	$ (1,816)	$ (999)