Restructuring Plans - Schedule of Plan Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	27 Months Ended
May 02, 2020	May 04, 2019	May 02, 2020
Restructuring Reserve [Roll Forward]
Charged to expense	$ 12.7	$ 26.8
Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	12.4
Payments and other adjustments	(12.0)
Charged to expense	12.3	$ 26.8	$ 217.3
Ending balance	12.7		12.7
Termination benefits \| Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	2.0
Payments and other adjustments	(1.2)
Charged to expense	2.9		28.7
Ending balance	3.7		3.7
Store closure and other costs \| Signet Path to Brillance
Restructuring Reserve [Roll Forward]
Beginning balance	10.4
Payments and other adjustments	(10.8)
Charged to expense	9.4
Ending balance	$ 9.0		$ 9.0

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
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-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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