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- Definition

Convertible Debt Securities, Amortized Cost

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Convertible Debt Securities, Fair Value Disclosure

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Convertible Debt Securities, Unrealized Gains

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Convertible Debt Securities, Unrealized Losses

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Debt Securities, Trading, Amortized Cost

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Derivative Assets, Accumulated Gross Unrealized Gain, before Tax

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Derivative Assets, Accumulated Gross Unrealized Loss, before Tax

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Derivative Liabilities, Accumulated Gross Unrealized Gain, before Tax

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Derivative Liabilities, Accumulated Gross Unrealized Loss, before Tax

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Fair Value, Assets Measured on Recurring Basis

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Investments, Accumulated Gross Unrealized Gain, before Tax

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Investments, Accumulated Gross Unrealized Loss, before Tax

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Trading Securities, Accumulated Gross Unrealized Gain, before Tax

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Trading Securities, Accumulated Gross Unrealized Loss, before Tax

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of investments in debt securities classified as trading.

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Financial Instruments (Cost and Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Apr. 30, 2018	Jan. 31, 2018	Apr. 30, 2017	Jan. 31, 2017
Cash equivalents
Amortized Cost	$ 1,093.0	$ 1,078.0	$ 1,340.2	$ 1,213.1
Marketable securities:
Amortized Cost	321.0
Short-term trading securities
Derivative contract assets, Amortized Cost	1.7	2.0
Derivative contract assets, Gross unrealized gains	10.6	7.5
Derivative contract assets, Gross unrealized losses	(1.0)	(1.3)
Derivative contract assets	11.3	8.2
Derivative contract liabilities, Amortized Cost	0.0	0.0
Derivative contract liabilities, Gross unrealized gains	0.0	0.0
Derivative contract liabilities, Gross unrealized losses	(5.1)	(26.6)
Derivative contract liabilities	(5.1)	(26.6)
Amortized Cost	1,039.5	1,080.2
Gross unrealized gains	18.5	17.0
Gross unrealized losses	(8.2)	(29.2)
Fair Value	1,049.8	1,068.0
Other asset
Short-term trading securities
Convertible debt securities, Amortized Cost	7.5	7.5
Convertible debt securities, Gross unrealized gains	1.2	0.5
Convertible debt securities, Gross unrealized losses	(0.3)	(0.2)
Convertible debt securities, Fair Value	8.4	7.8
Level 1
Short-term trading securities
Derivative contract assets	0.0	0.0
Derivative contract liabilities	0.0	0.0
Fair Value	236.8	392.1
Level 1 \| Other asset
Short-term trading securities
Convertible debt securities, Fair Value	0.0	0.0
Level 2
Short-term trading securities
Derivative contract assets	9.8	7.2
Derivative contract liabilities	(5.1)	(26.6)
Fair Value	803.1	667.1
Level 2 \| Other asset
Short-term trading securities
Convertible debt securities, Fair Value	0.0	0.0
Level 3
Short-term trading securities
Derivative contract assets	1.5	1.0
Derivative contract liabilities	0.0	0.0
Fair Value	9.9	8.8
Level 3 \| Other asset
Short-term trading securities
Convertible debt securities, Fair Value	8.4	7.8
Agency bonds
Cash equivalents
Amortized Cost		5.0
Fair Value		5.0
Agency bonds \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	13.7	13.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.1)	(0.1)
Fair Value	13.6	13.6
Agency bonds \| Level 1
Cash equivalents
Fair Value		5.0
Agency bonds \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	13.6
Agency bonds \| Level 2
Cash equivalents
Fair Value		0.0
Agency bonds \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	13.6	0.0
Agency bonds \| Level 3
Cash equivalents
Fair Value		0.0
Agency bonds \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Asset backed securities \| Marketable Securities, Current
Marketable securities:
Amortized Cost	9.2	13.1
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Fair Value	9.2	13.1
Asset backed securities \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	31.7	36.8
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.3)	(0.2)
Fair Value	31.4	36.6
Asset backed securities \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	0.0
Asset backed securities \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Asset backed securities \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	9.2	13.1
Asset backed securities \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	31.4	36.6
Asset backed securities \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	0.0
Asset backed securities \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Certificates of deposit
Cash equivalents
Amortized Cost	12.0	17.4
Fair Value	12.0	17.4
Certificates of deposit \| Marketable Securities, Current
Marketable securities:
Amortized Cost	3.1
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	3.1
Certificates of deposit \| Level 1
Cash equivalents
Fair Value	0.0	17.4
Certificates of deposit \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0
Certificates of deposit \| Level 2
Cash equivalents
Fair Value	12.0	0.0
Certificates of deposit \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	3.1
Certificates of deposit \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Certificates of deposit \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0
Commercial paper
Cash equivalents
Amortized Cost	451.9	324.2
Fair Value	451.9	324.2
Commercial paper \| Marketable Securities, Current
Marketable securities:
Amortized Cost		27.5
Gross Unrealized Gains		0.0
Gross Unrealized Losses		0.0
Fair Value		27.5
Commercial paper \| Level 1
Cash equivalents
Fair Value	0.0	0.0
Commercial paper \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value		0.0
Commercial paper \| Level 2
Cash equivalents
Fair Value	451.9	324.2
Commercial paper \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value		27.5
Commercial paper \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Commercial paper \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value		0.0
Corporate debt securities
Cash equivalents
Amortized Cost		5.0
Fair Value		5.0
Corporate debt securities \| Marketable Securities, Current
Marketable securities:
Amortized Cost	83.2	99.4
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.2)	(0.1)
Fair Value	83.0	99.3
Corporate debt securities \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	88.5	100.2
Gross Unrealized Gains	0.2	0.1
Gross Unrealized Losses	(0.7)	(0.4)
Fair Value	88.0	99.9
Corporate debt securities \| Level 1
Cash equivalents
Fair Value		5.0
Corporate debt securities \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	99.3
Corporate debt securities \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	99.9
Corporate debt securities \| Level 2
Cash equivalents
Fair Value		0.0
Corporate debt securities \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	83.0	0.0
Corporate debt securities \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	88.0	0.0
Corporate debt securities \| Level 3
Cash equivalents
Fair Value		0.0
Corporate debt securities \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	0.0
Corporate debt securities \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Custody cash deposit
Cash equivalents
Amortized Cost	2.2	5.2
Fair Value	2.2	5.2
Custody cash deposit \| Level 1
Cash equivalents
Fair Value	2.2	5.2
Custody cash deposit \| Level 2
Cash equivalents
Fair Value	0.0	0.0
Custody cash deposit \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Municipal bonds
Cash equivalents
Amortized Cost	5.0	5.0
Fair Value	5.0	5.0
Municipal bonds \| Marketable Securities, Current
Marketable securities:
Amortized Cost	4.2	9.2
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Fair Value	4.2	9.2
Municipal bonds \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	12.0	12.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.2)	(0.1)
Fair Value	11.8	12.6
Municipal bonds \| Level 1
Cash equivalents
Fair Value	0.0	5.0
Municipal bonds \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	7.7
Municipal bonds \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	12.6
Municipal bonds \| Level 2
Cash equivalents
Fair Value	5.0	0.0
Municipal bonds \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	4.2	1.5
Municipal bonds \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	11.8	0.0
Municipal bonds \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Municipal bonds \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	0.0
Municipal bonds \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Money market funds
Cash equivalents
Amortized Cost	175.2	278.8
Fair Value	175.2	278.8
Money market funds \| Level 1
Cash equivalents
Fair Value	175.2	0.0
Money market funds \| Level 2
Cash equivalents
Fair Value	0.0	278.8
Money market funds \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Sovereign debt
Cash equivalents
Amortized Cost	11.0	2.0
Fair Value	11.0	2.0
Sovereign debt \| Marketable Securities, Current
Marketable securities:
Amortized Cost	5.0
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	5.0
Sovereign debt \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost		2.8
Gross Unrealized Gains		0.0
Gross Unrealized Losses		0.0
Fair Value		2.8
Sovereign debt \| Level 1
Cash equivalents
Fair Value	0.0	0.0
Sovereign debt \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0
Sovereign debt \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value		0.0
Sovereign debt \| Level 2
Cash equivalents
Fair Value	11.0	2.0
Sovereign debt \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	5.0
Sovereign debt \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value		2.8
Sovereign debt \| Level 3
Cash equivalents
Fair Value	0.0	0.0
Sovereign debt \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0
Sovereign debt \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value		0.0
U.S. government securities
Cash equivalents
Amortized Cost	6.5
Fair Value	6.5
U.S. government securities \| Marketable Securities, Current
Marketable securities:
Amortized Cost	36.1	37.1
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.1)	0.0
Fair Value	36.0	37.1
U.S. government securities \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	22.7	25.5
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(0.2)	(0.2)
Fair Value	22.5	25.3
U.S. government securities \| Level 1
Cash equivalents
Fair Value	0.0
U.S. government securities \| Level 1 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	37.1
U.S. government securities \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	25.3
U.S. government securities \| Level 2
Cash equivalents
Fair Value	6.5
U.S. government securities \| Level 2 \| Marketable Securities, Current
Marketable securities:
Fair Value	36.0	0.0
U.S. government securities \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	22.5	0.0
U.S. government securities \| Level 3
Cash equivalents
Fair Value	0.0
U.S. government securities \| Level 3 \| Marketable Securities, Current
Marketable securities:
Fair Value	0.0	0.0
U.S. government securities \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0	0.0
Mutual funds
Short-term trading securities
Amortized Cost	52.9	50.1
Gross Unrealized Gains	6.5	8.9
Gross Unrealized Losses	0.0	0.0
Fair Value	59.4	59.0
Mutual funds \| Level 1
Short-term trading securities
Fair Value	59.4	59.0
Mutual funds \| Level 2
Short-term trading securities
Fair Value	0.0	0.0
Mutual funds \| Level 3
Short-term trading securities
Fair Value	0.0	$ 0.0
Other Securities \| Marketable Securities, Noncurrent
Marketable securities:
Amortized Cost	4.2
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	4.2
Other Securities \| Level 1 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	0.0
Other Securities \| Level 2 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	4.2
Other Securities \| Level 3 \| Marketable Securities, Noncurrent
Marketable securities:
Fair Value	$ 0.0