Accrued expenses and other current liabilities - Additional Information (Detail)	12 Months Ended
Feb. 02, 2019
Payables and Accruals [Abstract]
Lifetime diamond guarantee inspection period	6 months

US Division Required Inspection Period For Lifetime Gemstone Guarantee

No definition available.

Name:	sig_USDivisionRequiredInspectionPeriodForLifetimeGemstoneGuarantee
Namespace Prefix:	sig_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration