Loans, Overdrafts and Long-Term Debt - Additional Information (Detail)			3 Months Ended		12 Months Ended
	May 19, 2014 USD ($)	May 15, 2014 USD ($)	Feb. 03, 2018 USD ($)	Oct. 28, 2017 USD ($)	Feb. 03, 2018 USD ($)	Jan. 28, 2017 USD ($)	Jan. 30, 2016 USD ($)	Sep. 12, 2017 USD ($)	Jul. 29, 2017 USD ($)	Apr. 30, 2016 USD ($)
Debt Instrument [Line Items]
Amortization related to capitalized fees					$ 3,700,000	$ 2,800,000	$ 3,600,000
Payment of debt issuance costs					1,400,000	2,700,000	0
Bank overdrafts			$ 14,200,000		14,200,000	14,200,000
Term Loan
Debt Instrument [Line Items]
Proceeds from debt, net of issuance costs					350,000,000	0	$ 0
Senior Unsecured Notes Due in 2024 | Signet UK Finance plc
Debt Instrument [Line Items]
Capitalized fees			7,000,000		7,000,000
Capitalized issuance costs written off			2,600,000		2,600,000	1,900,000
Amortization related to capitalized fees					700,000	700,000
Face amount	$ 400,000,000
Stated interest rate	4.70%
Proceeds from debt, net of issuance costs	$ 393,900,000
Bridge Loan
Debt Instrument [Line Items]
Payment of debt issuance costs				$ 1,400,000
Interest expense, debt				$ 900,000
Bridge Loan | R2Net Inc.
Debt Instrument [Line Items]
Long-term debt, gross								$ 350,000,000
Credit Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity									$ 700,000,000	$ 400,000,000
Capitalized fees, current			1,400,000		1,400,000
Capitalized fees			2,600,000		2,600,000
Capitalized issuance costs written off			1,200,000		1,200,000	800,000
Amortization related to capitalized fees					400,000	400,000
Stand-by letters of credit			$ 15,700,000		$ 15,700,000	$ 15,300,000
Weighted average interest rate			2.46%		2.46%	1.71%
Covenant, maximum leverage ratio					2.50
Covenant, minimum coverage ratio					1.40
Credit Facility | Term Loan
Debt Instrument [Line Items]
Capitalized fees, current			$ 700,000		$ 700,000
Capitalized fees			6,200,000		6,200,000
Capitalized issuance costs written off			$ 3,500,000		3,500,000	$ 2,700,000
Amortization related to capitalized fees					$ 800,000	$ 900,000
Weighted average interest rate			2.42%		2.42%	1.78%
Face amount			$ 357,500,000.0		$ 357,500,000.0
Credit Facility | Term Loan | Year One
Debt Instrument [Line Items]
Quarterly repayment rate			5.00%		5.00%
Credit Facility | Term Loan | Year Two
Debt Instrument [Line Items]
Quarterly repayment rate			7.50%		7.50%
Credit Facility | Term Loan | Year Three
Debt Instrument [Line Items]
Quarterly repayment rate			10.00%		10.00%
Credit Facility | Term Loan | Year Four
Debt Instrument [Line Items]
Quarterly repayment rate			12.50%		12.50%
Credit Facility | Term Loan | Year Five
Debt Instrument [Line Items]
Quarterly repayment rate			15.00%		15.00%
Securitization Facility
Debt Instrument [Line Items]
Capitalized issuance costs written off			$ 3,400,000		$ 3,400,000	$ 3,100,000
Amortization related to capitalized fees			$ 200,000		$ 300,000	$ 700,000
Weighted average interest rate			2.50%		2.50%	2.05%
Face amount		$ 600,000,000
Debt instrument, term		2 years
Debt issuance cost			$ 3,400,000		$ 3,400,000