Restructuring Plans - Schedule of Plan Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	15 Months Ended
May 04, 2019	May 05, 2018	May 04, 2019
Restructuring Reserve [Roll Forward]
Charged to expense	$ 5.4	$ 0.0
Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	12.6
Payments and other adjustments	(27.1)
Charged to expense	26.8	$ 6.5	$ 152.7
Ending balance	12.3		12.3
Termination benefits \| Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	0.0
Payments and other adjustments	(2.0)
Charged to expense	8.8		18.5
Ending balance	6.8		6.8
Store closure and other costs \| Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	12.6
Payments and other adjustments	(25.1)
Charged to expense	18.0		72.0
Ending balance	$ 5.5		$ 5.5

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
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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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
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-Topic 420
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-Section 50
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