XML 66 R59.htm IDEA: XBRL DOCUMENT v2.4.1.9

Goodwill and Intangible Assets (Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Indefinite-lived Intangible Assets by Segment [Line Items]
Franchise rights impairment	$ 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	$ 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	$ 4.2us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill
Franchise rights - indefinite-lived	348.1us-gaap_IndefiniteLivedFranchiseRights	329.3us-gaap_IndefiniteLivedFranchiseRights
Franchise rights [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Date of annual goodwill and indefinite lived intangible assets impairment test	April 30	April 30	April 30
Nonrecurring [Member] | Franchise rights [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Franchise rights impairment	0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_FranchiseRightsMember	0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_FranchiseRightsMember	4.2us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_FranchiseRightsMember
Franchise rights impairment, after tax			2.6an_ImpairmentOfIntangibleAssetsIndefiniteLivedExcludingGoodwillNetOfTax / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsNonrecurringMember / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_FranchiseRightsMember
AN Reportable Segment, Domestic [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Franchise rights - indefinite-lived	25.9us-gaap_IndefiniteLivedFranchiseRights / us-gaap_StatementBusinessSegmentsAxis = an_ANReportableSegmentDomesticMember
AN Reportable Segment, Import [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Franchise rights - indefinite-lived	122.8us-gaap_IndefiniteLivedFranchiseRights / us-gaap_StatementBusinessSegmentsAxis = an_ANReportableSegmentImportMember
AN Reportable Segment, Premium Luxury [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Franchise rights - indefinite-lived	$ 199.4us-gaap_IndefiniteLivedFranchiseRights / us-gaap_StatementBusinessSegmentsAxis = an_ANReportableSegmentPremiumLuxuryMember

X

- Definition

The date of the annual goodwill and indefinite-lived franchise rights impairment test.

+ References

No definition available.

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X

- Definition

The amount of impairment loss recognized in the period, resulting from the write-down of the carrying amount of an indefinite-lived intangible asset, other than goodwill, to fair value, net of taxes.

+ References

No definition available.

+ Details

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X

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

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- Definition

Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through a franchise arrangement having an indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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