Condensed Consolidated Statement of Operations (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Nov. 01, 2014	Nov. 02, 2013	Nov. 01, 2014	Nov. 02, 2013
Condensed Financial Statements, Captions [Line Items]
Sales	$ 1,177.9	$ 771.4	$ 3,459.9	$ 2,645.2
Cost of sales	(832.0)	(532.2)	(2,297.8)	(1,713.5)
Gross margin	345.9	239.2	1,162.1	931.7
Selling, general and administrative expenses	(388.7)	(233.4)	(1,078.4)	(770.9)
Other operating income, net	53.5	45.8	161.2	139.1
Operating (loss) income	10.7	51.6	244.9	299.9
Interest expense, net	(12.6)	(0.9)	(28.1)	(2.8)
(Loss) income before income taxes	(1.9)	50.7	216.8	297.1
Income taxes	0.6	(17.1)	(63.5)	(104.3)
Net (loss) income	(1.3)	33.6	153.3	192.8
Eliminations
Condensed Financial Statements, Captions [Line Items]
Equity in income of subsidiaries	73.1	(84.6)	(312.0)	(518.5)
Net (loss) income	73.1	(84.6)	(312.0)	(518.5)
Signet Jewelers Limited
Condensed Financial Statements, Captions [Line Items]
Selling, general and administrative expenses	(0.8)	(0.7)	(1.6)	(1.8)
Other operating income, net		0.1		0.1
Operating (loss) income	(0.8)	(0.6)	(1.6)	(1.7)
(Loss) income before income taxes	(0.8)	(0.6)	(1.6)	(1.7)
Equity in income of subsidiaries	(0.5)	34.2	154.9	194.5
Net (loss) income	(1.3)	33.6	153.3	192.8
Signet UK Finance plc
Condensed Financial Statements, Captions [Line Items]
Intercompany interest income (expense)	4.7		8.5
Interest expense, net	(5.0)		(8.9)
(Loss) income before income taxes	(0.3)		(0.4)
Income taxes	0.1		0.1
Net (loss) income	(0.2)		(0.3)
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Sales	1,161.1	761.0	3,412.3	2,613.0
Cost of sales	(828.9)	(531.1)	(2,287.9)	(1,710.6)
Gross margin	332.2	229.9	1,124.4	902.4
Selling, general and administrative expenses	(380.7)	(233.5)	(1,056.4)	(769.7)
Other operating income, net	56.9	43.2	162.9	138.2
Operating (loss) income	8.4	39.6	230.9	270.9
Intercompany interest income (expense)	(43.3)	(8.4)	(85.1)	(25.5)
Interest expense, net	(5.2)	(0.9)	(14.8)	(2.8)
(Loss) income before income taxes	(40.1)	30.3	131.0	242.6
Income taxes	13.0	(12.5)	(56.2)	(94.4)
Equity in income of subsidiaries	(50.2)	29.7	72.9	173.3
Net (loss) income	(77.3)	47.5	147.7	321.5
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Sales	16.8	10.4	47.6	32.2
Cost of sales	(3.1)	(1.1)	(9.9)	(2.9)
Gross margin	13.7	9.3	37.7	29.3
Selling, general and administrative expenses	(7.2)	0.8	(20.4)	0.6
Other operating income, net	(3.4)	2.5	(1.7)	0.8
Operating (loss) income	3.1	12.6	15.6	30.7
Intercompany interest income (expense)	38.6	8.4	76.6	25.5
Interest expense, net	(2.4)		(4.4)
(Loss) income before income taxes	39.3	21.0	87.8	56.2
Income taxes	(12.5)	(4.6)	(7.4)	(9.9)
Equity in income of subsidiaries	(22.4)	20.7	84.2	150.7
Net (loss) income	$ 4.4	$ 37.1	$ 164.6	$ 197.0