CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (24.2)	$ (82.4)
Other comprehensive loss, net of reclassifications:
Net gain on derivative instruments (net of tax effect of ($0.3) and ($0.7), respectively)	3.3
Net gain on derivative instruments (net of tax effect of ($0.3) and ($0.7), respectively)		6.0
Change in net unrealized gain on available-for-sale debt securities (net of tax effect of ($0.4) and $0.1, respectively)	1.1	0.6
Change in defined benefit pension items (net of tax effect of $0.1 and ($1.4), respectively)	(0.6)	7.7
Net change in cumulative foreign currency translation loss (net of tax effect of $0.4 and $0.3, respectively)	(10.4)	(24.3)
Total other comprehensive loss	(6.6)	(10.0)
Total comprehensive loss	$ (30.8)	$ (92.4)