INTANGIBLE ASSETS AND GOODWILL INTANGIBLE ASSETS AND GOODWILL - AMORTIZATION AND IMPAIRMENT (Details) - USD ($)
3 Months Ended
Apr. 30, 2018
Apr. 30, 2017
Finite-Lived Intangible Assets    
Amortization of intangible assets $ 15,100,000 $ 21,100,000
Impairment of goodwill 0 0
Impairment of acquired intangible assets $ 0 $ 0