Note 7 - Related Party Transactions (Details Textual) xbrli-pure in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Related Party Transaction, Expenses from Transactions with Related Party	$ 407,000	$ 275,000
Operating Lease, Cost	343,000
Revenue from Related Parties	582,000	659,000
Sonic Financial [Member]
Related Party Transaction, Expenses from Transactions with Related Party	407,000	275,000
Due from Affiliates	0		$ 0
Sonic Financial [Member] \| Oil Chem [Member]
Due from Related Parties, Total	114,000		217,000
Affiliated Entity [Member]
Operating Lease, Cost	183,000
Operating Leases, Rent Expense, Total		182,000
Sonic Automotive Inc. [Member]
Due from Affiliates	94,000		$ 142,000
Revenue from Related Parties	$ 235,000	$ 221,000
Number of Vehicles Sold	0	0
Sonic Automotive Inc. [Member] \| SMI Properties [Member]
Revenue from Related Parties	$ 165,000	$ 159,000
Sonic Automotive Inc. [Member] \| Oil Chem [Member]
Revenue from Related Parties	$ 347,000	$ 438,000

The number of vehicles sold.

No definition available.

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Period Type:	duration

- Definition

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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