CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (566.9)	$ (582.1)	$ (330.5)
Other comprehensive loss, net of reclassifications:
Net loss on derivative instruments (net of tax effect of $3.2, ($1.1), and $0.6)	(31.2)	(1.1)	(27.1)
Change in net unrealized (loss) gain on available-for-sale securities (net of tax effect of $0.1, ($0.5), and $0.0)	(0.2)	1.3	(1.4)
Change in defined benefit pension items (net of tax effect of ($0.7), ($0.9), and $0.9)	4.5	(5.5)	(4.6)
Net change in cumulative foreign currency translation gain (loss) (net of tax effect of ($4.8), $0.2, and $0.5)	81.6	(52.1)	(34.7)
Total other comprehensive income (loss)	54.7	(57.4)	(67.8)
Total comprehensive loss	$ (512.2)	$ (639.5)	$ (398.3)