Condensed consolidating financial information - Condensed consolidated income statement (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
May 02, 2015	May 03, 2014
Condensed Income Statements, Captions [Line Items]
Sales	$ 1,530.6us-gaap_SalesRevenueNet	$ 1,056.1us-gaap_SalesRevenueNet
Cost of sales	(964.7)us-gaap_CostOfGoodsSold	(648.9)us-gaap_CostOfGoodsSold
Gross margin	565.9us-gaap_GrossProfit	407.2us-gaap_GrossProfit
Selling, general and administrative expenses	(453.2)	(310.5)
Other operating income, net	63.5us-gaap_OtherOperatingIncome	54.0us-gaap_OtherOperatingIncome
Operating income	176.2us-gaap_OperatingIncomeLoss	150.7us-gaap_OperatingIncomeLoss
Intra-entity interest income (expense)	0us-gaap_InterestIncomeRelatedParty	0us-gaap_InterestIncomeRelatedParty
Interest expense, net	(11.0)us-gaap_InterestExpense	(1.8)us-gaap_InterestExpense
Income before income taxes	165.2	148.9
Income taxes	(46.4)us-gaap_IncomeTaxExpenseBenefit	(52.3)us-gaap_IncomeTaxExpenseBenefit
Equity in income of subsidiaries	0	0
Net income	118.8us-gaap_NetIncomeLoss	96.6us-gaap_NetIncomeLoss
Consolidation, Eliminations
Condensed Income Statements, Captions [Line Items]
Sales	0	0
Cost of sales	0	0
Gross margin	0	0
Selling, general and administrative expenses	0	0
Other operating income, net	0	0
Operating income	0	0
Intra-entity interest income (expense)	0	0
Interest expense, net	0	0
Income before income taxes	0	0
Income taxes	0	0
Equity in income of subsidiaries	(272.3)	(269.0)
Net income	(272.3)	(269.0)
Signet Jewelers Limited \| Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Sales	0	0
Cost of sales	0	0
Gross margin	0	0
Selling, general and administrative expenses	(0.3)	(0.4)
Other operating income, net	0	0
Operating income	(0.3)	(0.4)
Intra-entity interest income (expense)	0	0
Interest expense, net	0	0
Income before income taxes	(0.3)	(0.4)
Income taxes	0	0
Equity in income of subsidiaries	119.1	97.0
Net income	118.8	96.6
Signet UK Finance plc \| Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Sales	0	0
Cost of sales	0	0
Gross margin	0	0
Selling, general and administrative expenses	0	0
Other operating income, net	0	0
Operating income	0	0
Intra-entity interest income (expense)	4.7	0
Interest expense, net	(4.9)	0
Income before income taxes	(0.2)	0
Income taxes	0	0
Equity in income of subsidiaries	0	0
Net income	(0.2)	0
Guarantor Subsidiaries \| Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Sales	1,511.0	1,043.7
Cost of sales	(961.0)	(647.6)
Gross margin	550.0	396.1
Selling, general and administrative expenses	(444.2)	(303.8)
Other operating income, net	63.5	52.0
Operating income	169.3	144.3
Intra-entity interest income (expense)	(46.1)	(7.0)
Interest expense, net	(3.5)	(1.8)
Income before income taxes	119.7	135.5
Income taxes	(48.5)	(55.9)
Equity in income of subsidiaries	76.0	91.2
Net income	147.2	170.8
Non-Guarantor Subsidiaries \| Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Sales	19.6	12.4
Cost of sales	(3.7)	(1.3)
Gross margin	15.9	11.1
Selling, general and administrative expenses	(8.7)	(6.3)
Other operating income, net	0	2.0
Operating income	7.2	6.8
Intra-entity interest income (expense)	41.4	7.0
Interest expense, net	(2.6)	0
Income before income taxes	46.0	13.8
Income taxes	2.1	3.6
Equity in income of subsidiaries	77.2	80.8
Net income	$ 125.3	$ 98.2

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Total costs related to goods produced and sold during the reporting period.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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