Name:	an_ContractsInTransitAndVehicleReceivables
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Balance Type:	debit
Period Type:	instant

The amount due to the company from manufacturers or distributors, within one year of the balance sheet date, including (1) rebates and assistance for holdbacks, floorplan interest and advertising expenses; (2) incentives based on achieving certain objectives; and (3) amounts due for warranty and service work performed for customers.

No definition available.

Name:	an_ManufacturerReceivables
Namespace Prefix:	an_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount due to the company from outside sources, within one year of the balance sheet date, for parts and automotive repair and maintenance services that have been delivered or sold, excluding amounts due from manufacturers. Also includes amounts due from finance organizations, within one year of the balance sheet date, for commissions on the sale of financing products.

No definition available.

Name:	an_TradeReceivables
Namespace Prefix:	an_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02(3)(a)(1))
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-Topic 310
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-Topic 310
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Period Type:	instant

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.5-02(4))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-4

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Balance Type:	credit
Period Type:	instant

Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
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-Name Accounting Standards Codification
-Topic 942
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-Paragraph 1
-Subparagraph (SX 210.9-03.10)
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-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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Balance Type:	debit
Period Type:	instant

Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

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

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10