Financial Instruments, Fair Value and Risk Management - Summary of Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions	Jul. 31, 2016	Jan. 31, 2016	Jan. 29, 2016	Oct. 31, 2015
Assets measured at fair value
Available-for-sale securities	$ 1.5			$ 1.4
Held-for-trading securities	1.6			1.7
Total assets	3.1			3.1
Liabilities measured at fair value
Earnout liability	38.7	$ 31.1	$ 36.0	0.0
Total liabilities	40.1			7.6
Foreign exchange forward contracts
Liabilities measured at fair value
Foreign exchange forward contracts	1.4			7.6
Level 1
Assets measured at fair value
Available-for-sale securities	1.5			1.4
Held-for-trading securities	0.0			0.0
Total assets	1.5			1.4
Liabilities measured at fair value
Earnout liability	0.0			0.0
Total liabilities	0.0			0.0
Level 1 | Foreign exchange forward contracts
Liabilities measured at fair value
Foreign exchange forward contracts	0.0			0.0
Level 2
Assets measured at fair value
Available-for-sale securities	0.0			0.0
Held-for-trading securities	1.6			1.7
Total assets	1.6			1.7
Liabilities measured at fair value
Earnout liability	0.0			0.0
Total liabilities	1.4			7.6
Level 2 | Foreign exchange forward contracts
Liabilities measured at fair value
Foreign exchange forward contracts	1.4			7.6
Level 3
Assets measured at fair value
Available-for-sale securities	0.0			0.0
Held-for-trading securities	0.0			0.0
Total assets	0.0			0.0
Liabilities measured at fair value
Earnout liability	38.7			0.0
Total liabilities	38.7			0.0
Level 3 | Foreign exchange forward contracts
Liabilities measured at fair value
Foreign exchange forward contracts	$ 0.0			$ 0.0