Annual report pursuant to Section 13 and 15(d)

Description of Business and Summary of Significant Accounting Policies - Additional Information (Details)

v3.20.4
Description of Business and Summary of Significant Accounting Policies - Additional Information (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
USD ($)
State
reporting_unit
Store
Dealerships
Segment
Brand
Collision
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Number of operating segments | Segment 2    
Number of new vehicle dealerships | Dealerships 96    
Number of states | State 12    
Number of different brands of cars and light trucks | Brand 21    
Number of collision repair centers | Collision 14    
Operating lease liabilities $ 338,903    
ROU assets 330,322 $ 337,842  
Revenue allowances for commission reserves 34,200 32,000  
Amount recognized for floor plan assistance $ 40,600 41,500 $ 42,200
Term for funding of finance contracts 10 days    
Contracts in transit included in receivables, net $ 179,700 230,900  
Receivables, net $ 371,666 432,742  
Number of reporting units | reporting_unit 2    
Goodwill $ 213,977 475,791 509,592
Insurance reserves 25,800 23,100  
Concentrations of credit risk with respect to receivables are limited primarily to receivables from automobile manufacturers 80,200 94,800  
Advertising expense 42,200 60,800 63,100
Cooperative manufacturer credits advertising expenses $ 19,200 25,300 $ 26,700
Number of reportable Segment | Segment 2    
Income Tax Benefit Goodwill Impairment $ 51,300    
Financial institutions      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Concentrations of credit risk with respect to receivables are limited primarily to receivables from financial institutions 208,800 $ 258,700  
Franchise assets      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Franchise asset impairment charge 0    
Continuing operations | Franchise assets      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Franchise asset impairment charge $ 0    
Dealership      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Percentage of dealership that is accounted for under the equity method 50.00%    
Franchised dealerships      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Goodwill $ 147,300    
EchoPark      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Goodwill $ 66,700    
Franchised dealerships      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Number of Stores | Store 84    
EchoPark      
Description Of Business And Summary Of Significant Accounting Policies [Line Items]      
Number of Stores | Store 16