INTANGIBLE ASSETS AND GOODWILL - INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Jan. 31, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 768,898	$ 778,675
Finite-Lived Intangible Assets, Accumulated Amortization	(586,395)	(580,911)
Intangible assets with finite lives, Net	182,503	197,764
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	458,725	465,130
Finite-Lived Intangible Assets, Accumulated Amortization	(330,492)	(328,069)
Intangible assets with finite lives, Net	128,233	137,061
Acquired Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	291,603	294,841
Finite-Lived Intangible Assets, Accumulated Amortization	(243,894)	(241,585)
Intangible assets with finite lives, Net	47,709	53,256
Trade Names
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	12,823	12,957
Finite-Lived Intangible Assets, Accumulated Amortization	(7,411)	(6,783)
Intangible assets with finite lives, Net	5,412	6,174
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)	(4,440)
Intangible assets with finite lives, Net	0	0
Noncompete Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	1,307	1,307
Finite-Lived Intangible Assets, Accumulated Amortization	(158)	(34)
Intangible assets with finite lives, Net	$ 1,149	$ 1,273