Document and Entity Information - shares	9 Months Ended
	Nov. 03, 2018	Nov. 30, 2018
Document And Entity Information [Abstract]
Document type	10-Q
Amendment flag	false
Document period end date	Nov. 03, 2018
Document fiscal year focus	2019
Document fiscal period focus	Q3
Trading symbol	SIG
Entity registrant name	SIGNET JEWELERS LTD
Entity Central Index Key	0000832988
Entity Emerging Growth Company	false
Entity Small Business	false
Current Fiscal Year End Date	--02-02
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares outstanding		51,912,259