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.

No definition available.

+ Details

Name:	us-gaap_LossContingenciesLineItems
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Balance Type:	na
Period Type:	duration

- Definition

Amount of damages paid to the plaintiff in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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Balance Type:	credit
Period Type:	duration

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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Balance Type:	na
Period Type:	duration

- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_LitigationCaseAxis=sig_EnvironmentalProtectionAgencyCollectiveActionMember
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- Details

Name:	srt_LitigationCaseAxis=sig_S.D.N.Y.CasesMember
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- Details

Name:	srt_CounterpartyNameAxis=sig_ConsumerFInancialProtectionBureauMember
Namespace Prefix:
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Name:	srt_CounterpartyNameAxis=sig_NewYorkAttorneyGeneralMember
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Commitments and contingencies - Additional information (Details)					1 Months Ended			12 Months Ended
	Mar. 27, 2019 lawsuit	Jan. 15, 2018 plaintiff	Jan. 14, 2018 plaintiff	Aug. 01, 2016 employee	Feb. 28, 2019 USD ($)	Mar. 31, 2017 lawsuit	Aug. 31, 2016 lawsuit	Feb. 03, 2018 employee
EPA Collective Action
Loss Contingencies [Line Items]
Number of employees opted in lawsuit (employee) (plaintiff)		254	70,000	10,314				9,124
S.D.N.Y. Cases
Loss Contingencies [Line Items]
New claims filed, number \| lawsuit	2					2	2
Consumer FInancial Protection Bureau
Loss Contingencies [Line Items]
Loss contingency, damages paid, value					$ 10,000,000
New York Attorney General
Loss Contingencies [Line Items]
Loss contingency, damages paid, value					$ 1,000,000