Goodwill and Intangible Assets (Gross Carrying Amount and Related Accumulated Amortization of Definite-lived Intangible Assets) (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amount (As Restated)	$ 23,739	$ 26,655	$ 14,225
Accumulated Amortization (As Restated)	(10,783)	(8,165)	(6,069)
Net (As Restated)	12,956	18,490	8,156
Existing Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amount (As Restated)	7,144	8,870	7,840
Accumulated Amortization (As Restated)	(6,265)	(5,239)	(4,164)
Net (As Restated)	879	3,631	3,676
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amount (As Restated)	12,628	14,128	3,494
Accumulated Amortization (As Restated)	(2,641)	(1,271)	(525)
Net (As Restated)	9,987	12,857	2,969
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Amount (As Restated)	3,967	3,657	2,891
Accumulated Amortization (As Restated)	(1,877)	(1,655)	(1,380)
Net (As Restated)	$ 2,090	$ 2,002	$ 1,511