INTANGIBLE ASSETS AND GOODWILL - INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		$ 668,619
Finite-Lived Intangible Assets, Accumulated Amortization	$ (520,034)	(434,460)
Finite-Lived Intangible Assets, Net	226,093	234,159
Finite and Indefinite-Lived Intangible Assets Gross	746,127	669,719
Intangible assets, net	226,093	235,259
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	438,664	403,657
Finite-Lived Intangible Assets, Accumulated Amortization	(281,592)	(244,792)
Finite-Lived Intangible Assets, Net	157,072	158,865
Acquired Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	273,156	233,982
Finite-Lived Intangible Assets, Accumulated Amortization	(212,571)	(168,653)
Finite-Lived Intangible Assets, Net	60,585	65,329
Trade Names
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	26,820	23,493
Finite-Lived Intangible Assets, Accumulated Amortization	(18,570)	(14,187)
Finite-Lived Intangible Assets, Net	8,250	9,306
Non-competition Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	3,047	3,047
Finite-Lived Intangible Assets, Accumulated Amortization	(2,861)	(2,499)
Finite-Lived Intangible Assets, Net	186	548
Distribution network
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	4,440	4,440
Finite-Lived Intangible Assets, Accumulated Amortization	(4,440)	(4,329)
Finite-Lived Intangible Assets, Net	$ 0	111
In Process Research and Development
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization		0
Indefinite-Lived Intangible Assets (Excluding Goodwill)		$ 1,100