v2.4.0.8
Summary of Significant Accounting Policies - Additional Information (Details) (USD $)
 9 Months Ended 12 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Finite-Lived Intangible Assets          
Reserve for estimated returns, discounts and allowances $ 30,500,000   $ 24,700,000 $ 22,800,000  
Revenue recognition period for lifetime extended warranties     3 years    
Shipping and handling revenue     25,600,000 23,900,000 17,300,000
Reserve for uncollectible accounts 14,100,000   9,500,000 8,300,000  
Amortization expense 9,000,000 7,100,000 9,500,000 7,900,000 4,200,000
Future Amortization Expense Recognized In Current Fiscal Year 13,000,000        
Estimated annual amortization expense, 2013 14,200,000   8,800,000    
Estimated annual amortization expense, 2014 12,800,000   7,900,000    
Estimated annual amortization expense, 2015 11,400,000   7,100,000    
Estimated annual amortization expense, 2016 10,500,000   6,300,000    
Estimated annual amortization expense, 2017     6,000,000    
Self-insurance reserve, total     44,100,000 37,400,000  
Self-insurance reserve, current     21,500,000 18,200,000  
Claims deposits     500,000 500,000  
Percentage threshold to measure tax benefit     50.00%    
Equity Method Investment, Ownership Percentage 49.00%        
Equity method investment, ownership percentage of other investors 51.00%        
Equity Method Investments 9,300,000        
Self-insurance
          
Finite-Lived Intangible Assets          
Outstanding letters of credit     37,100,000 31,800,000  
Salvage Mechanical Products
          
Finite-Lived Intangible Assets          
Standard warranty period 6 months   6 months    
Remanufactured Engines
          
Finite-Lived Intangible Assets          
Standard warranty period 3 years   3 years    
Sator
          
Finite-Lived Intangible Assets          
Intangible assets recognized 49,978,000        
Euro Car Parts Holdings Limited
          
Finite-Lived Intangible Assets          
Intangible assets recognized       43,723,000  
Trade names and trademarks
          
Finite-Lived Intangible Assets          
Intangible assets recognized     600,000 40,100,000  
Trade names and trademarks | Minimum
          
Finite-Lived Intangible Assets          
Useful life, years 10 years   10 years    
Trade names and trademarks | Maximum
          
Finite-Lived Intangible Assets          
Useful life, years 30 years   30 years    
Trade names and trademarks | Sator
          
Finite-Lived Intangible Assets          
Intangible assets recognized 24,700,000        
Trade names and trademarks | Euro Car Parts Holdings Limited
          
Finite-Lived Intangible Assets          
Intangible assets recognized       39,300,000  
Customer relationships
          
Finite-Lived Intangible Assets          
Intangible assets recognized     4,100,000 5,700,000  
Customer relationships | Minimum
          
Finite-Lived Intangible Assets          
Useful life, years 5 years   5 years    
Customer relationships | Maximum
          
Finite-Lived Intangible Assets          
Useful life, years 15 years   10 years    
Customer relationships | Sator
          
Finite-Lived Intangible Assets          
Intangible assets recognized 25,300,000        
Covenants not to compete
          
Finite-Lived Intangible Assets          
Intangible assets recognized     $ 600,000 $ 1,500,000  
Covenants not to compete | Minimum
          
Finite-Lived Intangible Assets          
Useful life, years 1 year   1 year    
Covenants not to compete | Maximum
          
Finite-Lived Intangible Assets          
Useful life, years 5 years   5 years