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

Intangible Assets and Goodwill - Changes in Carrying Amount of Franchise Assets and Goodwill (Detail)

v2.4.1.9

Intangible Assets and Goodwill - Changes in Carrying Amount of Franchise Assets and Goodwill (Detail) (USD $)	0 Months Ended	12 Months Ended
	Oct. 02, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Indefinite-lived Intangible Assets [Line Items]
Franchise Assets, Reductions from impairment		$ (2,200,000)
Net Goodwill, Beginning balance		476,315,000us-gaap_Goodwill	454,224,000us-gaap_Goodwill
Net Goodwill, Additions through current year acquisitions		10,176,000us-gaap_GoodwillAcquiredDuringPeriod	22,091,000us-gaap_GoodwillAcquiredDuringPeriod
Net Goodwill, Prior year acquisition allocations		(3,000)
Net Goodwill, Reductions from dispositions		(10,559,000)
Net Goodwill, Reductions from impairment	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Net Goodwill, Ending balance		475,929,000us-gaap_Goodwill	476,315,000us-gaap_Goodwill	454,224,000us-gaap_Goodwill
Franchise Assets [Member]
Indefinite-lived Intangible Assets [Line Items]
Franchise Assets, Beginning balance		79,535,000	60,635,000
Franchise Assets, Additions through current year acquisitions		7,500,000	19,500,000
Franchise Assets, Reductions from dispositions		(7,735,000)
Franchise Assets, Reductions from impairment		(2,200,000)	(600,000)
Franchise Assets, Ending balance		$ 77,100,000	$ 79,535,000

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

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No definition available.

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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- Definition

Amount of write-off of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit associated with the sale of all or a portion of a reporting unit.

+ References

No definition available.

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