Debt Instrument, Number Of Counterparties

No definition available.

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- Definition

Debt Instrument, Number Of Manufacturer Affiliated Finance Companies

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Redemption Price, Percentage Of Principal Amount Redeemable

+ References

No definition available.

+ Details

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- Definition

The amount of notes payable attributable to the floor plan.

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Accordian Feature, Increase Limit

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Option To Reallocate Commitment, Maximum Aggregate Commitment Threshold Percentage

+ References

No definition available.

+ Details

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- Definition

The number of financial institutions.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The number of manufacturer affiliated finance companies.

+ References

No definition available.

+ Details

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- Definition

The fixed interest rate percentage on total mortgage debt.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Paragraph 3
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Credit Facilities and Long-term Debt - Narrative (Details)					12 Months Ended
	Oct. 09, 2020 USD ($)	Jul. 14, 2020 USD ($) financial_institution finance_company	Dec. 09, 2019 USD ($)	Jul. 24, 2017 USD ($)	Dec. 31, 2020 USD ($) finance_company financial_institution	Jul. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Debt instrument, number of counter-parties \| finance_company		2
Floor plan notes payable					$ 234,200,000		$ 425,200,000
Floor Plan Notes Payable \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage					5.25%
Line of Credit \| Credit Facility
Debt Instrument [Line Items]
Number of financial institutions \| financial_institution					19
Number of manufacturer affiliated finance companies \| finance_company					7
Total financing commitment					$ 2,800,000,000
Higher borrowing capacity option					3,200,000,000
Other debt
Debt Instrument [Line Items]
Total long-term debt outstanding					$ 2,400,000		3,100,000
Other debt \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage					4.40%
Other debt \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage					5.30%
Real Estate Mortgages
Debt Instrument [Line Items]
Percent of total mortgage debt that is fixed					76.20%
Total long-term debt outstanding					$ 611,500,000		597,700,000
Real Estate Mortgages \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage					1.90%
Real Estate Mortgages \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage					5.30%
Senior Notes \| 5.250% Senior notes due 2025
Debt Instrument [Line Items]
Interest rate, stated percentage				5.25%
Total long-term debt outstanding					$ 300,000,000.0		300,000,000.0
Aggregate principal amount				$ 300,000,000.0
Redemption percentage price				100.00%
Percentage of principal amount redeemable				101.00%
Senior Notes \| 4.625% Senior notes due 2027
Debt Instrument [Line Items]
Interest rate, stated percentage			4.625%
Total long-term debt outstanding					400,000,000.0		400,000,000.0
Aggregate principal amount			$ 400,000,000.0
Percentage of principal amount redeemable			101.00%
Senior Notes \| 4.375% Senior notes due 2031
Debt Instrument [Line Items]
Interest rate, stated percentage	4.375%
Total long-term debt outstanding					$ 550,000,000.0		0
Aggregate principal amount	$ 550,000,000.0
Percentage of principal amount redeemable	101.00%
Senior Notes \| Option One \| 4.625% Senior notes due 2027
Debt Instrument [Line Items]
Redemption percentage price			100.00%
Senior Notes \| Option One \| 4.375% Senior notes due 2031
Debt Instrument [Line Items]
Redemption percentage price	100.00%
Senior Notes \| Option Two \| 4.625% Senior notes due 2027
Debt Instrument [Line Items]
Redemption percentage price			40.00%
Senior Notes \| Option Two \| 4.375% Senior notes due 2031
Debt Instrument [Line Items]
Redemption percentage price	40.00%
Finance Lease Obligations \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage					1.90%
Finance Lease Obligations \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage					8.50%
Used Vehicle Inventory Financing Facility \| Line of Credit
Debt Instrument [Line Items]
Annual interest rate (in percent)					1.54%
Total long-term debt outstanding					$ 0		149,000,000.0
Used Vehicle Inventory Financing Facility \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)					1.40%
Used Vehicle Inventory Financing Facility \| Line of Credit \| Credit Facility
Debt Instrument [Line Items]
Option to reallocate commitment, maximum aggregate commitment threshold percentage					16.50%
Revolving Lines of Credit \| Line of Credit
Debt Instrument [Line Items]
Total long-term debt outstanding					$ 39,000,000.0		$ 0
Revolving Lines of Credit \| Line of Credit \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)					1.00%
Revolving Lines of Credit \| Line of Credit \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)					2.00%
Revolving Lines of Credit \| Line of Credit \| Credit Facility
Debt Instrument [Line Items]
Option to reallocate commitment, maximum aggregate commitment threshold percentage					18.75%
Service Loaner Floor Plan \| Line of Credit
Debt Instrument [Line Items]
Annual interest rate (in percent)					1.34%
Service Loaner Floor Plan \| Line of Credit \| Credit Facility
Debt Instrument [Line Items]
Total financing commitment					$ 100,000,000
New Vehicle Floor Plan \| Line of Credit
Debt Instrument [Line Items]
Annual interest rate (in percent)					1.24%
New Vehicle Floor Plan \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)					1.10%
New Vehicle Floor Plan \| Line of Credit \| Credit Facility
Debt Instrument [Line Items]
Accordion feature, increase limit					$ 400,000,000
Other Lines of Credit
Debt Instrument [Line Items]
Total financing commitment					80,000,000.0
Long-term line of credit					$ 0
Other Lines of Credit \| Maximum
Debt Instrument [Line Items]
Annual interest rate (in percent)					5.70%
Other Lines of Credit \| Line of Credit
Debt Instrument [Line Items]
Annual interest rate (in percent)					1.14%
Securitization Facility
Debt Instrument [Line Items]
Total financing commitment						$ 150,000,000.0
Long-term debt					$ 39,000,000.0
Real Estate Backed Credit Facility Member
Debt Instrument [Line Items]
Total financing commitment		$ 251,500,000
Debt term		5 years
Debt instrument, number of counter-parties \| financial_institution		8
Real Estate Backed Credit Facility Member \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		0.75%
Real Estate Backed Credit Facility Member \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		2.00%
Real Estate Backed Credit Facility Member \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (in percent)		2.50%