Note 6 - Details of Financial Covenants (Details) $ in Millions	Dec. 31, 2015 USD ($)
Current ratio, requirement	1.1
Current ratio	1.26
Fixed charge coverage ratio, requirement	1.2
Fixed charge coverage ratio	3.36
Leverage ratio, requirement	5
Leverage ratio	1.79
Funded debt restriction	$ 600.0
Funded debt	$ 413.4

A ratio of current assets divided by current liabilities.

No definition available.

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- Definition

An ratio defined in the credit agreement as current assets divided by current liabilities. Under the credit agreement, the company is required to remain in compliance with this minimum current ratio.

+ References

No definition available.

+ Details

Name:	lad_DebtCovenantCurrentRatio
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- Definition

A ratio defined in the credit agreement as fixed charges divided by earnings before interest, taxes, depreciation, amortization and rent (EBITDAR). Under the credit agreement, the company is required to remain in compliance with this minimum fixed charge coverage ratio.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
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Period Type:	instant

- Definition

Represents the debt covenant, funded debt restriction. Under the credit agreement, the company is required to comply with this maximum.

+ References

No definition available.

+ Details

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Namespace Prefix:	lad_
Data Type:	xbrli:monetaryItemType
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- Definition

A ratio defined in the credit agreement as funded debt divided by earnings before interest, taxes, depreciation, amortization and rent (EBITDAR). Under the credit agreement, the company is required to remain in compliance with this maximum leverage ratio.

+ References

No definition available.

+ Details

Name:	lad_DebtCovenantLeverageRatio
Namespace Prefix:	lad_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

A ratio defined in the credit agreement as fixed charges divided by earnings before interest, taxes, depreciation, amortization and rent (EBITDAR).

+ References

No definition available.

+ Details

Name:	lad_FixedChargeCoverageRatio
Namespace Prefix:	lad_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

A ratio defined in the credit agreement as funded debt divided by earnings before interest, taxes, depreciation, amortization and rent (EBITDAR).

+ References

No definition available.

+ Details

Name:	lad_LeverageRatio
Namespace Prefix:	lad_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant