Related Party Transaction - Additional Information (Details) $ in Millions	12 Months Ended
	Jan. 31, 2018 USD ($)	Jan. 31, 2017 USD ($)	Jan. 31, 2016 USD ($)	Oct. 31, 2017 ft²
Related Party Transaction [Line Items]
Rent expense	$ 1.9	$ 2.0	$ 1.7
One of Board of Director
Related Party Transaction [Line Items]
Public relations service fee	0.2	$ 0.3
Fiserv Solutions, LLC
Related Party Transaction [Line Items]
Lease rentable space of office building | ft²				33,400
Rent expense	$ 0.2