CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (142.8)	$ (43.8)	$ (408.7)	$ (293.3)
Other comprehensive loss, net of reclassifications:
Net loss on derivative instruments (net of tax effect of $0.2, $0.0, ($0.6) and ($0.7), respectively)	(0.7)	(12.1)	(11.7)	(22.2)
Change in net unrealized (loss) gain on available-for-sale securities (net of tax effect of $0.0, $0.0, ($0.6) and $0.2, respectively)	(1.6)	(0.4)	1.8	(1.6)
Change in defined benefit pension items (net of tax effect of $0.0, $0.0, ($0.2) and $0.0, respectively)	0.3	0.3	0.6	1.3
Net change in cumulative foreign currency translation loss (net of tax effect of ($0.5), ($4.5), ($0.5) and $0.0, respectively)	(55.7)	(4.0)	(57.1)	(10.7)
Total other comprehensive loss	(57.7)	(16.2)	(66.4)	(33.2)
Total comprehensive loss	$ (200.5)	$ (60.0)	$ (475.1)	$ (326.5)