Sonic Automotive, Inc. Annual report pursuant to Section 13 and 15(d)

Related Parties - Additional Information (Detail)

v3.6.0.2

Related Parties - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SFC [Member]
Related Party Transaction [Line Items]
Aggregate annual rent for leased aircraft usage	$ 0.5	$ 0.6	$ 0.5
Oil Chem Research Company [Member]
Related Party Transaction [Line Items]
Purchase from related party	2.1	2.1	2.1
SMISC Holdings, Inc. [Member]
Related Party Transaction [Line Items]
Purchase from related party	0.9
Speedway Motorsports, Inc. [Member]
Related Party Transaction [Line Items]
Vehicle sales to related party	0.2
Aggregate annual rent for leased aircraft usage	$ 0.8	$ 0.8	$ 0.6
Messrs. O. Bruton Smith, B. Scott Smith, David Bruton Smith and Marcus G. Smith [Member] \| Speedway Motorsports, Inc. [Member]
Related Party Transaction [Line Items]
Ownership percentage	70.00%
Messrs. O. Bruton Smith [Member] \| Speedway Motorsports, Inc. [Member]
Related Party Transaction [Line Items]
Related party transaction amount	$ 1.5
B. Scott Smith [Member] \| Speedway Motorsports, Inc. [Member]
Related Party Transaction [Line Items]
Related party transaction amount	0.6
David Bruton Smith and Marcus G. Smith [Member] \| Speedway Motorsports, Inc. [Member]
Related Party Transaction [Line Items]
Related party transaction amount	$ 0.1
Minimum [Member] \| Mr. Marcus G. Smith [Member] \| SFC [Member]
Related Party Transaction [Line Items]
Ownership percentage	10.00%

- Definition

Beneficial ownership interest percentage.

+ References

No definition available.

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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.

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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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.

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- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Related Parties
-URI http://asc.fasb.org/extlink&oid=16382449

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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