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Accounts Receivable, Threshold To Bear Interest, Period

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Debt Instrument, Number Of Counterparties

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Debt Instrument, Number Of Manufacturer Affiliated Finance Companies

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Financing Receivable, Less Than 60 Days Past Due, Percent

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The number of the new vehicle brands.

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Restricted Cash On Deposit In Reserve Accounts

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Amount of allowance for credit loss of accounts and financing receivables. Includes, but is not limited to, notes and loan receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of nonaccrual financing receivable balance outstanding that is past due.

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No definition available.

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Amount of interest capitalized during the period.

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The number of countries in which the entity operates as of balance sheet date.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The number of states the entity operates in as of the balance sheet date.

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Represents the number of stores.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) brand store country segment state	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2021 USD ($)	Apr. 29, 2021 finance_company financialInstitution	Sep. 30, 2020 USD ($)	Jul. 14, 2020 finance_company
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of stores \| store	278
Number of new vehicle brands \| brand	40
Number of countries \| country	2
Number of states \| state	25
Debt Instrument [Line Items]
Threshold period for interest to bear on receivables	60 days
Interest costs capitalized	$ 2,000,000	$ 1,600,000	$ 2,300,000
Restricted cash on deposit in reserve accounts, included in other non-current assets	3,700,000	0	$ 0
Debt instrument, number of manufacturer-affiliated finance companies \| finance_company							2
Accrued warranty balance				$ 600,000		$ 500,000
Contract liability	239,000,000	194,100,000
Contract liability, revenue recognized	35,000,000	31,100,000
Contract asset	$ 9,600,000	$ 8,200,000
Number of reportable segments \| segment	3
Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Debt instrument, number of counter-parties \| financialInstitution					20
Debt instrument, number of manufacturer-affiliated finance companies \| finance_company					8
Loans receivables \| Automobile loan
Debt Instrument [Line Items]
Loan receivables aged less than 60 days past due, percent (more than)		95.00%
Loan receivable on non-accrual status, percent (less than)		5.00%
Allowance for credit losses	$ 25,000,000
Minimum
Debt Instrument [Line Items]
Period that contracts in transit are outstanding	5 days
Maximum
Debt Instrument [Line Items]
Period that contracts in transit are outstanding	10 days