XML 65 R54.htm IDEA: XBRL DOCUMENT
v3.21.2

Financial Instruments And Fair Value Measurements (Nonfinancial Assets Measured on a Nonrecurring Basis) (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain/(Loss) on goodwill | $ 0 | $ 0 |  | $ 0 | $ (318,300,000) |
Equity investment | 56,700,000 |  |  | 56,700,000 |  |
Gain/(Loss) on equity investment | 3,400,000 |  |  |  |  |
Goodwill impairment | 0 | 0 |  | 0 | 318,300,000 |
Franchise rights impairment | 0 | 0 |  | 0 | 57,500,000 |
Continuing Operations [Member] | Reported Value Measurement [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Assets held for sale | 81,300,000 |  |  | 81,300,000 |  | $ 25,500,000
Discontinued Operations [Member] | Reported Value Measurement [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Assets held for sale in discontinued operations | 1,100,000 |  |  | 1,100,000 |  | $ 8,000,000.0
Franchise Rights [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Franchise rights impairment |  |  |  | 0 |  |
Fair Value, Nonrecurring [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain/(Loss) on goodwill |  |  | $ (318,300,000) | 0 | (318,300,000) |
Gain/(Loss) on franchise rights and other |  |  |  | 0 | (59,900,000) |
Gain/(Loss) on equity investment |  |  |  | 3,400,000 | 0 |
Gain/(Loss) on right-of-use assets |  |  |  | (100,000) | (400,000) |
Gain/(Loss) on assets held and used |  |  |  | (1,600,000) | (5,800,000) |
Goodwill impairment |  |  | 318,300,000 | 0 | 318,300,000 |
Fair Value, Nonrecurring [Member] | Other Intangible Assets [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Impairment of finite-lived intangibles assets |  |  |  |  | 2,400,000 |
Fair Value, Nonrecurring [Member] | Franchise Rights [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Franchise rights impairment |  |  | 57,500,000 |  |  |
Fair Value, Nonrecurring [Member] | Reporting Unit, Premium Luxury [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain/(Loss) on goodwill |  |  | (257,400,000) |  |  |
Goodwill impairment |  |  | 257,400,000 |  |  |
Fair Value, Nonrecurring [Member] | Reporting Unit, Collision Centers [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain/(Loss) on goodwill |  |  | (41,600,000) |  |  |
Goodwill impairment |  |  | 41,600,000 |  |  |
Fair Value, Nonrecurring [Member] | Reporting Unit, Parts Centers [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain/(Loss) on goodwill |  |  | (19,300,000) |  |  |
Goodwill impairment |  |  | 19,300,000 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Goodwill | 0 | 457,500,000 |  | 0 | 457,500,000 |
Franchise rights and other | 0 | 26,200,000 |  | 0 | 26,200,000 |
Equity investment | 53,400,000 | 0 |  | 53,400,000 | 0 |
Right-of-use assets | 0 | 1,400,000 |  | 0 | 1,400,000 |
Long-lived assets held and used | $ 10,400,000 | $ 1,800,000 |  | $ 10,400,000 | $ 1,800,000 |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Franchise rights and other |  |  | $ 24,600,000 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Weighted Average Cost of Capital [Member] | Average [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.085 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Discount Rate [Member] | Minimum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.111 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Discount Rate [Member] | Maximum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.143 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Discount Rate [Member] | Average [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.121 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Long-term Revenue Growth Rate [Member] | Average [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.020 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Minimum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.006 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Maximum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.028 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Long-term Pretax Income Margin [Member] | Average [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.014 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Contributory Asset Charges [Member] | Minimum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.042 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Contributory Asset Charges [Member] | Maximum [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.121 |  |  |
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Franchise Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Contributory Asset Charges [Member] | Average [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Abstract] |  |  |  |  |  |
Franchise rights, measurement input |  |  | 0.062 |  |  |

X
- Definition Value of input used to measure franchise rights. + References No definition available. + Details
Name: | an_FranchiseRightsMeasurementInput
Namespace Prefix: | an_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value portion of right-of-use assets. + References No definition available. + Details
Name: | an_RightofUseAssetFairValueDisclosure
Namespace Prefix: | an_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5C -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2473-110228 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 + Details
Name: | us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2473-110228 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5B -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1107-107759 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714 + Details
Name: | us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714 + Details
Name: | us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_FairValueInputsQuantitativeInformationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_GoodwillFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266 + Details
Name: | us-gaap_GoodwillImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
Name: | us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
Name: | us-gaap_ImpairmentOfIntangibleAssetsFinitelived
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
Name: | us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
Name: | us-gaap_ImpairmentOfLongLivedAssetsHeldForUse
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwillFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of loss from impairment of right-of-use asset from operating lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 25 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121593497&loc=SL77918431-209957 + Details
Name: | us-gaap_OperatingLeaseImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_PropertyPlantAndEquipmentFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementOperatingActivitiesSegmentAxis=us-gaap_SegmentContinuingOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementOperatingActivitiesSegmentAxis=us-gaap_SegmentDiscontinuedOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_FranchiseRightsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_OtherIntangibleAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ReportingUnitAxis=an_ReportingUnitPremiumLuxuryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ReportingUnitAxis=an_ReportingUnitCollisionCentersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ReportingUnitAxis=an_ReportingUnitPartsCentersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=an_MeasurementInputWeightedAverageCostofCapitalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_ArithmeticAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputLongTermRevenueGrowthRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=an_MeasurementInputLongtermPretaxIncomeMarginMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=an_MeasurementInputContributoryAssetChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |