Commitments and Contingencies - Litigation (Detail) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Jan. 31, 2014 USD ($)	Jan. 31, 2014 CHF	Jan. 31, 2014	Jan. 31, 2013	Apr. 30, 2015 Swatch Parties [Member] USD ($)	Apr. 30, 2015 Swatch Parties [Member] CHF	Apr. 30, 2015 Tiffany Parties [Member] USD ($)	Apr. 30, 2015 Tiffany Parties [Member] CHF
Loss Contingencies [Line Items]
Minimum Damage Claim Sought							$ 128.0	120.0
Maximum Damage Claim Sought							575.0	540.0
Minimum Damage Claim Sought By Third Party					78.0	73.0
Maximum Damage Claim Sought By Third Party					4,000.0	3,800.0
Loss Contingency, Damages Paid, Value		402.7
Branded Watch Sales As Percentage Of Net Sales			1.00%	1.00%
Arbitration award expense	$ 480.2