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Share-Based Plans - Board of Directors (Details) (Nonemployee Board of Directors [Member])
 12 Months Ended
Jan. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]  
Deferred Compensation Arrangement with Individual, Fair Value of Shares Issued to Each Individual 110,000big_DeferredCompensationArrangementWithIndividualFairValueOfSharesIssuedToEachIndividual
Director Stock Option Plan [Member]  
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]  
Share-based Compensation Arrangement by Share-based Payment Award, Annual Shares Issued 10,000big_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualSharesIssued
/ us-gaap_PlanNameAxis
= big_DirectorStockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= big_NonemployeeBoardOfDirectorsMember
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period 3 years
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Shares Vested on First Anniversary 20.00%big_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesVestedOnFirstAnniversary
/ us-gaap_PlanNameAxis
= big_DirectorStockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= big_NonemployeeBoardOfDirectorsMember
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Shares Vested on Second Anniversary 60.00%big_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesVestedOnSecondAnniversary
/ us-gaap_PlanNameAxis
= big_DirectorStockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= big_NonemployeeBoardOfDirectorsMember
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Shares Vested on Third Anniversary 100.00%big_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesVestedOnThirdAnniversary
/ us-gaap_PlanNameAxis
= big_DirectorStockOptionPlanMember
/ us-gaap_TitleOfIndividualAxis
= big_NonemployeeBoardOfDirectorsMember
Share-based Compensation Arrangement by Share-based Payment Award, Award Term Following Termination of Employment, Death, or Disability 1 year
Share Based Compensation Arrangement By Share Based Payment Award, Award Expiration Period From Grant Date 10 years 1 month