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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_OtherRestructuringCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Restructuring Plans - Restructuring and Related Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 04, 2018	Jul. 29, 2017	Aug. 04, 2018	Jul. 29, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ (77.4)	$ 0.0
Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Inventory charges(1)	$ 63.2		63.2
Restructuring charges	(82.8)	$ 0.0	(89.3)	0.0
Signet Path to Brillance \| Cost of Sales
Restructuring Cost and Reserve [Line Items]
Inventory charges(1)	63.2	0.0		0.0
Signet Path to Brillance \| Restructuring Charges
Restructuring Cost and Reserve [Line Items]
Other Plan related expenses	$ 19.6	$ 0.0	$ 26.1	$ 0.0