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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures incurred for purchase and construction of assets7false 5us-gaap_PropertyPlantAndEquipmentAdditionsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse1070000010700000USD$falsetruefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26truefalsefalse3170000031700000USD$falsetruefalsexbrli:monetaryItemTypemonetaryAcquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.No definition available.false2Acquisition of fixed assets8false 5gpi_NumberOfDealershipsAcquiredgpi_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2323falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerNumber of dealerships acquired.No definition available.false256Number of dealerships acquiredfalseDetail of Certain Balance Sheet Accounts (Property and Equipment) (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.group1auto.com/role/DetailOfCertainBalanceSheetAccountsPropertyAndEquipmentDetails268