CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (330.5)	$ 81.8	$ 228.8
Other comprehensive (loss) income, net of reclassifications:
Net (loss) gain on derivative instruments (net of tax effect of $0.6, ($0.7), and $1.1)	(27.1)	39.3	0.7
Change in net unrealized loss on available-for-sale securities (net of tax effect of $0.0, ($0.2), and $0.3)	(1.4)	(0.2)	(1.1)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(4.6)	(16.0)	5.4
Net change in cumulative foreign currency translation (loss) gain (net of tax effect of $0.5, $4.9, and$2.1)	(34.7)	(75.8)	0.1
Total other comprehensive (loss) income	(67.8)	(52.7)	5.1
Total comprehensive (loss) income	$ (398.3)	$ 29.1	$ 233.9