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, 2019	Jan. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Amount	$ 30,902	$ 24,795
Accumulated Amortization	(14,609)	(14,211)
Net	16,293	10,584
Existing Technology
Finite-Lived Intangible Assets [Line Items]
Amount	9,203	7,290
Accumulated Amortization	(7,216)	(6,996)
Net	1,987	294
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amount	15,791	13,264
Accumulated Amortization	(5,508)	(4,834)
Net	10,283	8,430
Patented Technology
Finite-Lived Intangible Assets [Line Items]
Amount	5,908	4,241
Accumulated Amortization	(1,885)	(2,381)
Net	$ 4,023	$ 1,860