XML 64 R51.htm IDEA: XBRL DOCUMENT v3.3.0.814

Divestitures (Details) $ in Millions	3 Months Ended
	Mar. 31, 2015 USD ($) stores	Sep. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)
Import Stores Divested [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of stores divested | stores	2
Gain on disposal	$ 1.4	$ 4.0
Gain on disposal, net of taxes	$ 0.9	$ 2.5
Customer Lead Distribution Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on disposal			$ 8.4
Gain on disposal, net of taxes			$ 5.2

X

- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation, net of taxes.

+ References

No definition available.

+ Details

Name:	an_DisposalGroupNotDiscontinuedOperationGainLossonDisposalNetofTaxes
Namespace Prefix:	an_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The number of businesses divested during the period.

+ References

No definition available.

+ Details

Name:	an_Numberofbusinessesdivested
Namespace Prefix:	an_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 360



-SubTopic 10



-Section 45



-Paragraph 5



-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228



Reference 2: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 360



-SubTopic 10



-Section 50



-Paragraph 3



-Subparagraph (c)



-URI http://asc.fasb.org/extlink&oid=51719941&loc=d3e2941-110230

+ Details

Name:	us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal
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_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=an_ImportStoresDivestedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=an_CustomerLeadDistributionBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: