Note 18 - Equity-method Investments (Details Textual) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Oct. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Equity Method Investment Equity Contribution Obligation			$ 22,511
NMTC Program [Member]
Equity Method Investment, Ownership Percentage	99.90%
Payments to Acquire Equity Method Investments	$ 4,100	$ 22,800	$ 22,800
Equity Method Investment Equity Contribution Obligation	$ 49,800
Equity Method Investment Equity Contribution Obligation Term	2 years

Represents the equity contribution obligation associated with an equity method investment.

No definition available.

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Namespace Prefix:	lad_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the equity contribution obligation term associated with an equity method investment.

+ References

No definition available.

+ Details

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Namespace Prefix:	lad_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

+ Details

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- Details

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