Segments - Schedule of total revenue by geographic areas (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 41,488	$ 26,305	$ 109,478	$ 71,424
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	28,045	17,931	74,965	48,617
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	11,418	7,543	30,340	20,616
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Total	$ 2,025	$ 831	$ 4,173	$ 2,191