Restructuring Plans - Schedule of Plan Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	39 Months Ended
May 01, 2021	May 02, 2020	May 01, 2021
Restructuring Reserve [Roll Forward]
Charged (credited) to expense	$ (0.7)	$ 12.7
Signet Path to Brilliance
Restructuring Reserve [Roll Forward]
Beginning balance	10.2
Payments and other adjustments	(0.7)
Charged (credited) to expense	(0.7)	$ 12.3	$ 251.9
Ending balance	8.8		8.8
Termination benefits \| Signet Path to Brilliance
Restructuring Reserve [Roll Forward]
Beginning balance	2.1
Payments and other adjustments	(0.6)
Charged (credited) to expense	(0.7)		49.2
Ending balance	0.8		0.8
Store closure and other costs \| Signet Path to Brilliance
Restructuring Reserve [Roll Forward]
Beginning balance	8.1
Payments and other adjustments	(0.1)
Charged (credited) to expense	0.0
Ending balance	$ 8.0		$ 8.0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
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