Fair Value of Financial Instruments - Financial Assets and Liabilities Carried at Fair Value (Details) - USD ($) $ in Millions		Jan. 31, 2016	Jan. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, Fair Value		$ 78.5	$ 77.5
Total financial liabilities, Fair Value		17.2	5.3
Other assets, net [Member] | Marketable securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[1]	31.8	53.5
Short-term Investments [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[2]	43.0	1.5
Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.6	0.3
Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious metal collars [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.2
Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.6	15.1
Prepaid expenses and other current assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.3	7.1
Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	13.4	3.2
Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	2.4	0.1
Accounts Payable and Accrued Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	1.4	2.0
Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, Fair Value		78.5	77.5
Total financial liabilities, Fair Value		17.2	5.3
Carrying Value [Member] | Other assets, net [Member] | Marketable securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[1]	31.8	53.5
Carrying Value [Member] | Short-term Investments [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[2]	43.0	1.5
Carrying Value [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.6	0.3
Carrying Value [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious metal collars [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.2
Carrying Value [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.6	15.1
Carrying Value [Member] | Prepaid expenses and other current assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.3	7.1
Carrying Value [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	13.4	3.2
Carrying Value [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	2.4	0.1
Carrying Value [Member] | Accounts Payable and Accrued Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	1.4	2.0
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, Fair Value		74.8	55.0
Total financial liabilities, Fair Value		0.0	0.0
Level 1 [Member] | Other assets, net [Member] | Marketable securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[1]	31.8	53.5
Level 1 [Member] | Short-term Investments [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[2]	43.0	1.5
Level 1 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 1 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious metal collars [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0
Level 1 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 1 [Member] | Prepaid expenses and other current assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 1 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	0.0	0.0
Level 1 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	0.0	0.0
Level 1 [Member] | Accounts Payable and Accrued Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	0.0	0.0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, Fair Value		3.7	22.5
Total financial liabilities, Fair Value		17.2	5.3
Level 2 [Member] | Other assets, net [Member] | Marketable securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[1]	0.0	0.0
Level 2 [Member] | Short-term Investments [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[2]	0.0	0.0
Level 2 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.6	0.3
Level 2 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious metal collars [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.2
Level 2 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.6	15.1
Level 2 [Member] | Prepaid expenses and other current assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	1.3	7.1
Level 2 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	13.4	3.2
Level 2 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	2.4	0.1
Level 2 [Member] | Accounts Payable and Accrued Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	1.4	2.0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, Fair Value		0.0	0.0
Total financial liabilities, Fair Value		0.0	0.0
Level 3 [Member] | Other assets, net [Member] | Marketable securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[1]	0.0	0.0
Level 3 [Member] | Short-term Investments [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets, Fair Value	[2]	0.0	0.0
Level 3 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 3 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Precious metal collars [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0
Level 3 [Member] | Prepaid expenses and other current assets [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 3 [Member] | Prepaid expenses and other current assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value	[3]	0.0	0.0
Level 3 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Precious Metal Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	0.0	0.0
Level 3 [Member] | Accounts Payable and Accrued Liabilities [Member] | Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	0.0	0.0
Level 3 [Member] | Accounts Payable and Accrued Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value	[4]	$ 0.0	$ 0.0

[1] Included within Other assets, net.

[2] Included within Short-term investments.

[3] Included within Prepaid expenses and other current assets or Other assets, net evaluated based on the maturity of the contract.

[4] Included within Accounts payable and accrued liabilities or Other long-term liabilities evaluated based on the maturity of the contract.