Maturity date (by month and year) for debt instrument.

No definition available.

Name:	azo_DebtInstrumentMaturityMonthAndYear
Namespace Prefix:	azo_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

Name:	us-gaap_LongtermDebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesSixteenMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesNineMember
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Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesFourteenMember
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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesElevenMember
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Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesFifteenMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=azo_SeniorNotesSeventeenMember
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- Details

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Financing - Schedule of Debt (Parenthetical) (Detail)			12 Months Ended
Financing - Schedule of Debt (Parenthetical) (Detail)	Apr. 18, 2017	Apr. 29, 2015	Aug. 26, 2017	Aug. 27, 2016
Commercial paper, weighted average interest rate of 1.44% and 0.72% at August 26, 2017 and August 27, 2016, respectively [Member]
Debt Instrument [Line Items]
Weighted average interest rate of commercial paper			1.44%	0.72%
1.300% Senior Notes due January 2017, effective interest rate of 1.43% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			1.30%	1.30%
Effective interest rate			1.43%	1.43%
Debt instrument maturity, month and year			2017-01	2017-01
7.125% Senior Notes due August 2018, effective interest rate of 7.28% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			7.125%	7.125%
Effective interest rate			7.28%	7.28%
Debt instrument maturity, month and year			2018-08	2018-08
1.625% Senior Notes due April 2019, effective interest rate of 1.77% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			1.625%	1.625%
Effective interest rate			1.77%	1.77%
Debt instrument maturity, month and year			2019-04	2019-04
4.000% Senior Notes due November 2020, effective interest rate of 4.43% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			4.00%	4.00%
Effective interest rate			4.43%	4.43%
Debt instrument maturity, month and year			2020-11	2020-11
2.500% Senior Notes due April 2021, effective interest rate of 2.62% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage		2.50%	2.50%	2.50%
Effective interest rate			2.62%	2.62%
Debt instrument maturity, month and year		2021-04	2021-04	2021-04
3.700% Senior Notes due April 2022, effective interest rate of 3.85% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			3.70%	3.70%
Effective interest rate			3.85%	3.85%
Debt instrument maturity, month and year			2022-04	2022-04
2.875% Senior Notes due January 2023, effective interest rate of 3.21% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			2.875%	2.875%
Effective interest rate			3.21%	3.21%
Debt instrument maturity, month and year			2023-01	2023-01
3.125% Senior Notes due July 2023, effective interest rate of 3.26% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			3.125%	3.125%
Effective interest rate			3.26%	3.26%
Debt instrument maturity, month and year			2023-07	2023-07
3.250% Senior Notes due April 2025, effective interest rate 3.36% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage		3.25%	3.25%	3.25%
Effective interest rate			3.36%	3.36%
Debt instrument maturity, month and year		2025-04	2025-04	2025-04
3.125% Senior Notes due April 2026, effective interest rate of 3.28% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage			3.125%	3.125%
Effective interest rate			3.28%	3.28%
Debt instrument maturity, month and year			2026-04	2026-04
3.750% Senior Notes due June 2027, effective interest rate of 3.83% [Member]
Debt Instrument [Line Items]
Stated interest rate percentage	3.75%		3.75%	3.75%
Effective interest rate			3.83%	3.83%
Debt instrument maturity, month and year	2027-06		2027-06	2027-06