Effect of Derivative Instruments Designated as Cash Flow Hedges (Parenthetical) (Detail) (Cash Flow Hedging, Commodity Contract, USD $) In Millions, unless otherwise specified	12 Months Ended
Feb. 01, 2014
Cash Flow Hedging \| Commodity Contract
Derivative Instruments, Gain (Loss) [Line Items]
Losses related to change in fair value of commodity contracts terminated prior to contract maturity	$ 27.8

Derivative Instruments, Gain(Loss) Recognized In Other Comprehensive Income Effective Portion, Net, Related To Net, Terminated Contracts

No definition available.

Name:	sig_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNetRelatedToNetTerminatedContracts
Namespace Prefix:	sig_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration