Goodwil, Long-lived Assets, and Other Charges - Gross Carrying Amount and Related Accumulated Amortization of Definite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amount	$ 24,795	$ 24,501
Accumulated Amortization	(14,211)	(12,453)
Net	10,584	12,048
Existing Technology
Finite-Lived Intangible Assets [Line Items]
Amount	7,290	7,136
Accumulated Amortization	(6,996)	(6,553)
Net	294	583
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amount	13,264	12,987
Accumulated Amortization	(4,834)	(3,680)
Net	8,430	9,307
Patented Technology
Finite-Lived Intangible Assets [Line Items]
Amount	4,241	4,378
Accumulated Amortization	(2,381)	(2,220)
Net	$ 1,860	$ 2,158