Restructuring Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
May 05, 2018	Apr. 29, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 6.5	$ 0.0
Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring plan, length	3 years
Minimum \| Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 170.0
Cash payments	$ 105.0
Net reduction in net selling square feet, percent	4.00%
Maximum \| Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 190.0
Cash payments	$ 120.0
Net reduction in net selling square feet, percent	5.00%
Cost Reduction Activities \| Minimum \| Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 125.0
Cash payments	60.0
Cost Reduction Activities \| Maximum \| Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	135.0
Cash payments	$ 65.0

Restructuring Plan, Length

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- Definition

Restructuring Plan, Net Reduction in Net Selling Square Feet, Percent

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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