Leases - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Feb. 13, 2021	Aug. 29, 2020
Renewal options and lease term	Retail leases typically have initial terms of between one and 20 years, with one to six optional renewal periods of one to five years each.
Finance lease term	20 years
Accumulated amortization related to finance lease assets	$ 99.9	$ 107.3
Land and Building
Additional leases not yet commenced, undiscounted future payments	23.7
Vehicles
Additional leases not yet commenced, undiscounted future payments	$ 159.5
Minimum [Member]
Finance lease term	1 year
Operating lease commencement date	2021
Maximum [Member]
Finance lease term	5 years
Operating lease commencement date	2022

Lessee, operating and finance lease, lease not yet commenced, undiscounted future payments.

No definition available.

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Namespace Prefix:	azo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Operating lease commencement date.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Term of lessee's finance lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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