Fair Value of Financial Instruments - Financial Assets and Liabilities Carried at Fair Value (Details) - USD ($)		Apr. 30, 2020	Jan. 31, 2020	Apr. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, fair value		$ 77,600,000	$ 82,700,000	$ 99,400,000
Total financial liabilities, fair value		9,000,000.0	5,500,000	9,500,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, fair value		48,700,000	62,000,000.0	90,600,000
Total financial liabilities, fair value		0	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, fair value		28,900,000	20,700,000	8,800,000
Total financial liabilities, fair value		9,000,000.0	5,500,000	9,500,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets, fair value		0	0	0
Total financial liabilities, fair value		0	0	0
Precious metal forward contracts | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	4,700,000	200,000	800,000
Precious metal forward contracts | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	200,000
Precious metal forward contracts | Level 1 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Precious metal forward contracts | Level 1 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0
Precious metal forward contracts | Level 2 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	4,700,000	200,000	800,000
Precious metal forward contracts | Level 2 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	200,000
Precious metal forward contracts | Level 3 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Precious metal forward contracts | Level 3 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0
Foreign exchange forward contracts | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	1,200,000	500,000	100,000
Foreign exchange forward contracts | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	2,900,000	2,900,000	500,000
Foreign exchange forward contracts | Level 1 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Foreign exchange forward contracts | Level 1 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Foreign exchange forward contracts | Level 2 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	1,200,000	500,000	100,000
Foreign exchange forward contracts | Level 2 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	2,900,000	2,900,000	500,000
Foreign exchange forward contracts | Level 3 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Foreign exchange forward contracts | Level 3 | Accounts payable and accrued liabilities | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]	0	0	0
Cross-currency swaps | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]		1,900,000	8,100,000
Cross-currency swaps | Level 1 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]		0	0
Cross-currency swaps | Level 2 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]		1,900,000	8,100,000
Cross-currency swaps | Level 3 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities, fair value	[1]		0	0
Time deposits | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[2]	12,300,000	22,700,000	53,200,000
Time deposits | Level 1 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[2]	12,300,000	22,700,000	53,200,000
Time deposits | Level 2 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[2]	0	0	0
Time deposits | Level 3 | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[2]	0	0	0
Marketable securities | Other assets, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[3]	36,400,000	39,300,000	37,400,000
Marketable securities | Level 1 | Other assets, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[3]	36,400,000	39,300,000	37,400,000
Marketable securities | Level 2 | Other assets, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[3]	0	0	0
Marketable securities | Level 3 | Other assets, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	[3]	0	0	0
Precious metal forward contracts | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	8,900,000	13,000,000.0	3,300,000
Precious metal forward contracts | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	5,200,000
Precious metal forward contracts | Level 1 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	0
Precious metal forward contracts | Level 1 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0
Precious metal forward contracts | Level 2 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	8,900,000	13,000,000.0	3,300,000
Precious metal forward contracts | Level 2 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	5,200,000
Precious metal forward contracts | Level 3 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	0
Precious metal forward contracts | Level 3 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0
Foreign exchange forward contracts | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	1,700,000	2,700,000	3,400,000
Foreign exchange forward contracts | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	5,000,000.0	2,100,000	2,100,000
Foreign exchange forward contracts | Level 1 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	0
Foreign exchange forward contracts | Level 1 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	0
Foreign exchange forward contracts | Level 2 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	1,700,000	2,700,000	3,400,000
Foreign exchange forward contracts | Level 2 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	5,000,000.0	2,100,000	2,100,000
Foreign exchange forward contracts | Level 3 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	0
Foreign exchange forward contracts | Level 3 | Prepaid expenses and other current assets | Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0	0	$ 0
Cross-currency swaps | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	8,100,000
Cross-currency swaps | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]		2,900,000
Cross-currency swaps | Level 1 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	0
Cross-currency swaps | Level 1 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]		0
Cross-currency swaps | Level 2 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	8,100,000
Cross-currency swaps | Level 2 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]		2,900,000
Cross-currency swaps | Level 3 | Prepaid expenses and other current assets | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]	$ 0
Cross-currency swaps | Level 3 | Accounts payable and accrued liabilities | Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets, fair value	[4]		$ 0

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

[2] Included within Short-term investments.

[3] Included within Other assets, net.

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