Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Name:	us-gaap_PaymentsForRestructuring
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(1))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(d))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

Name:	us-gaap_RestructuringAndRelatedCostIncurredCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140864-122747

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: 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=118932676&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

Name:	us-gaap_RestructuringCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

Name:	us-gaap_RestructuringReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_RestructuringChargesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=ayi_ConsolidationofFacilitiesandReductioninEmployeeHeadcountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=ayi_StreamliningActivitiesRelatedtoSaleofBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_EmployeeSeveranceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_OtherRestructuringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ayi_RestructuringActivityByActionsYearAxis=ayi_Fiscal2019ActionsRestructuringActivityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ayi_RestructuringActivityByActionsYearAxis=ayi_Fiscal2018ActionsRestructuringActivityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ayi_RestructuringActivityByActionsYearAxis=ayi_Fiscal2017ActionsRestructuringActivityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Special Charges (Details) - USD ($) $ in Millions	12 Months Ended
Special Charges (Details) - USD ($) $ in Millions	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Restructuring Cost and Reserve [Line Items]
Special charges	$ 1.8	$ 5.6	$ 11.3
Restructuring Reserve [Roll Forward]
Remaining balance of severance reserve	10.1
Payments made during the period	(7.7)
Remaining balance of severance reserve	1.9	10.1
Special Charges
Restructuring Cost and Reserve [Line Items]
Special charges	1.8	5.6	11.3
Consolidation of facilities and reduction in employee headcount
Restructuring Cost and Reserve [Line Items]
Special charges		10.6
Streamlining activities related to sale of business
Restructuring Cost and Reserve [Line Items]
Special charges		(5.0)
Severance and employee-related costs
Restructuring Reserve [Roll Forward]
Incurred costs	(0.5)
Severance and employee-related costs \| Special Charges
Restructuring Cost and Reserve [Line Items]
Special charges	(0.5)	5.4	11.2
Other restructuring costs \| Special Charges
Restructuring Cost and Reserve [Line Items]
Special charges	2.3	0.2	$ 0.1
Fiscal 2019 Actions
Restructuring Reserve [Roll Forward]
Remaining balance of severance reserve	0.0
Payments made during the period	(0.6)
Remaining balance of severance reserve	1.3	0.0
Fiscal 2019 Actions \| Severance and employee-related costs
Restructuring Reserve [Roll Forward]
Incurred costs	1.9
Fiscal 2018 Actions
Restructuring Reserve [Roll Forward]
Remaining balance of severance reserve	9.2
Payments made during the period	(6.6)
Remaining balance of severance reserve	0.6	9.2
Fiscal 2018 Actions \| Severance and employee-related costs
Restructuring Reserve [Roll Forward]
Incurred costs	(2.0)
Fiscal 2017 Actions
Restructuring Reserve [Roll Forward]
Remaining balance of severance reserve	0.9
Payments made during the period	(0.5)
Remaining balance of severance reserve	0.0	$ 0.9
Fiscal 2017 Actions \| Severance and employee-related costs
Restructuring Reserve [Roll Forward]
Incurred costs	$ (0.4)