Interest and Other Expense, net (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Other Income and Expenses [Abstract]
Interest and investment expense, net	$ (54.0)	$ (52.1)	$ (34.5)
Gain (loss) on foreign currency	3.9	5.1	(3.3)
(Loss) gain on strategic investments	(3.3)	12.5	(16.4)
Other income	5.2	16.8	6.0
Interest and other expense, net	$ (48.2)	$ (17.7)	$ (48.2)

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894

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