Annual report pursuant to Section 13 and 15(d)

Income Taxes (Details 4)

v2.4.1.9
Income Taxes (Details 4) (USD $)
Dec. 28, 2014
Dec. 29, 2013
Income Tax Disclosure [Abstract]    
Valuation allowance $ 990,000us-gaap_DeferredTaxAssetsValuationAllowance $ 290,000us-gaap_DeferredTaxAssetsValuationAllowance
Federal alternative minimum tax credit 1,262,000us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax 1,262,000us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax
General business and other tax credits 5,100,000rrgb_DeferredTaxAssetsTaxCreditCarryforwardsGeneralBusinessAndOther  
Unrecognized tax benefits that would impact effective tax rate if recognized $ 300,000us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate