INTANGIBLE ASSETS AND GOODWILL - GOODWILL (Details) - USD ($)	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Goodwill activity
Goodwill, gross at the beginning of the period	$ 1,484,346,000	$ 1,455,164,000	$ 1,331,683,000
Accumulated impairment losses	(66,865,000)	(66,865,000)	(66,865,000)
Goodwill, net at the beginning of the period	1,388,299,000	1,264,818,000
Business combinations, including prior year adjustments	59,035,000	81,180,000
Foreign currency translation and other	(29,853,000)	42,301,000
Goodwill, net, at the end of the period	1,417,481,000	1,388,299,000	1,264,818,000
Goodwill Impairments
Impairments of goodwill	0	0	0
Customer Engagement
Goodwill activity
Goodwill, gross at the beginning of the period	1,326,370,000	1,307,136,000	1,188,022,000
Accumulated impairment losses	(56,043,000)	(56,043,000)	(56,043,000)
Goodwill, net at the beginning of the period	1,251,093,000	1,131,979,000
Business combinations, including prior year adjustments	48,225,000	77,345,000
Foreign currency translation and other	(28,991,000)	41,769,000
Goodwill, net, at the end of the period	1,270,327,000	1,251,093,000	1,131,979,000
Cyber Intelligence
Goodwill activity
Goodwill, gross at the beginning of the period	157,976,000	148,028,000	143,661,000
Accumulated impairment losses	(10,822,000)	(10,822,000)	(10,822,000)
Goodwill, net at the beginning of the period	137,206,000	132,839,000
Business combinations, including prior year adjustments	10,810,000	3,835,000
Foreign currency translation and other	(862,000)	532,000
Goodwill, net, at the end of the period	$ 147,154,000	$ 137,206,000	$ 132,839,000