$AYI
ACUITY BRANDS INC Stock $ayi

$ayi Overview Financials Valuation SEC Filings Company Website

2019 Q3 Form 10-K Financial Statement

#000114421519000114 Filed on October 29, 2019

Income Statement

Concept	2019 Q3	2018 Q3	2018 Q2
Revenue	$938.1M	$1.061B	$944.0M
YoY Change	-11.6%	10.82%	5.88%
Cost Of Revenue	$543.4M	$650.3M	$554.9M
YoY Change	-16.44%	18.09%	8.23%
Gross Profit	$394.7M	$411.9M	$389.1M
YoY Change	-4.18%	1.23%	2.69%
Gross Profit Margin	42.07%	38.81%	41.22%
Selling, General & Admin	$254.9M	$259.7M	$271.8M
YoY Change	-1.85%	8.89%	10.09%
% of Gross Profit	64.58%	63.05%	69.85%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$22.60M	$21.80M	$20.20M
YoY Change	3.67%	20.44%	1.0%
% of Gross Profit	5.73%	5.29%	5.19%
Operating Expenses	$262.6M	$267.7M	$271.8M
YoY Change	-1.91%	9.44%	10.09%
Operating Profit	$132.1M	$144.2M	$107.4M
YoY Change	-8.39%	-11.15%	-18.33%
Interest Expense	-$7.700M	-$9.000M	$8.900M
YoY Change	-14.44%	9.76%	4.71%
% of Operating Profit	-5.83%	-6.24%	8.29%
Other Income/Expense, Net	-$2.100M	-$2.200M	-$8.200M
YoY Change	-4.55%	0.0%	18.84%
Pretax Income	$120.5M	$137.1M	$99.20M
YoY Change	-12.11%	-3.65%	-20.39%
Income Tax	$25.70M	$32.30M	$26.20M
% Of Pretax Income	21.33%	23.56%	26.41%
Net Earnings	$96.10M	$108.2M	$73.00M
YoY Change	-11.18%	19.56%	-11.19%
Net Earnings / Revenue	10.24%	10.2%	7.73%
Basic Earnings Per Share	$2.43	$2.71	$1.81
Diluted Earnings Per Share	$2.42	$2.70	$1.80
COMMON SHARES
Basic Shares Outstanding			40.40M shares
Diluted Shares Outstanding			40.50M shares

Balance Sheet

Concept	2019 Q3	2018 Q3	2018 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$461.0M	$129.1M	$94.30M
YoY Change	257.09%	-58.5%	-50.29%
Cash & Equivalents	$461.0M	$129.1M	$94.30M
Short-Term Investments
Other Short-Term Assets	$79.00M	$32.30M	$32.40M
YoY Change	144.58%	-0.92%	-21.17%
Inventory	$340.8M	$411.8M	$406.5M
Prepaid Expenses
Receivables	$561.0M	$637.9M	$572.6M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.442B	$1.211B	$1.106B
YoY Change	19.05%	-2.77%	1.07%
LONG-TERM ASSETS
Property, Plant & Equipment	$277.3M	$286.7M	$288.0M
YoY Change	-3.28%	-0.35%	1.27%
Goodwill	$967.3M	$970.6M	$970.5M
YoY Change	-0.34%	7.74%	9.35%
Intangibles	$466.0M	$498.7M	$504.6M
YoY Change	-6.56%	11.12%	12.56%
Long-Term Investments	$0.00	$0.00	$0.00
YoY Change
Other Assets	$17.70M	$18.80M	$13.50M
YoY Change	-5.85%	42.42%	-16.67%
Total Long-Term Assets	$1.731B	$1.778B	$1.777B
YoY Change	-2.65%	7.48%	8.57%
TOTAL ASSETS
Total Short-Term Assets	$1.442B	$1.211B	$1.106B
Total Long-Term Assets	$1.731B	$1.778B	$1.777B
Total Assets	$3.172B	$2.989B	$2.882B
YoY Change	6.14%	3.08%	5.56%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$338.8M	$451.1M	$464.5M
YoY Change	-24.89%	14.17%	29.1%
Accrued Expenses	$248.2M	$231.2M	$206.0M
YoY Change	7.35%	12.56%	11.9%
Deferred Revenue	$4.700M	$4.800M
YoY Change	-2.08%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$9.100M	$400.0K	$1.600M
YoY Change	2175.0%	0.0%	300.0%
Total Short-Term Liabilities	$596.1M	$682.7M	$672.1M
YoY Change	-12.68%	13.61%	23.48%
LONG-TERM LIABILITIES
Long-Term Debt	$347.5M	$356.4M	$356.4M
YoY Change	-2.5%	-0.03%	0.03%
Other Long-Term Liabilities	$5.200M	$8.200M	$69.60M
YoY Change	-36.59%	32.26%	9.43%
Total Long-Term Liabilities	$352.7M	$364.6M	$426.0M
YoY Change	-3.26%	0.52%	1.45%
TOTAL LIABILITIES
Total Short-Term Liabilities	$596.1M	$682.7M	$672.1M
Total Long-Term Liabilities	$352.7M	$364.6M	$426.0M
Total Liabilities	$1.254B	$1.272B	$1.282B
YoY Change	-1.45%	3.08%	7.25%
SHAREHOLDERS EQUITY
Retained Earnings	$2.296B	$1.999B	$1.896B
YoY Change	14.84%	20.44%	20.4%
Common Stock	$930.5M	$906.8M	$899.7M
YoY Change	2.61%	2.87%	2.72%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$1.160B	$1.100B	$1.074B
YoY Change	5.45%	41.73%	38.44%
Treasury Stock Shares	14.30M shares	13.70M shares	13.68M shares
Shareholders Equity	$1.919B	$1.717B	$1.600B
YoY Change
Total Liabilities & Shareholders Equity	$3.172B	$2.989B	$2.882B
YoY Change	6.14%	3.08%	5.56%

Cashflow Statement

Concept	2019 Q3	2018 Q3	2018 Q2
OPERATING ACTIVITIES
Net Income	$96.10M	$108.2M	$73.00M
YoY Change	-11.18%	19.56%	-11.19%
Depreciation, Depletion And Amortization	$22.60M	$21.80M	$20.20M
YoY Change	3.67%	20.44%	1.0%
Cash From Operating Activities	$182.7M	$52.50M	$123.1M
YoY Change	248.0%	-62.12%	13.98%
INVESTING ACTIVITIES
Capital Expenditures	-$13.20M	-$11.40M	-$11.30M
YoY Change	15.79%	-5.79%	-41.75%
Acquisitions
YoY Change
Other Investing Activities	-$2.900M	$1.400M	-$137.8M
YoY Change	-307.14%		-137900.0%
Cash From Investing Activities	-$16.10M	-$10.00M	-$149.1M
YoY Change	61.0%	-17.36%	672.54%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-39.20M	-7.400M	-108.6M
YoY Change	429.73%	1.37%	-70.13%
NET CHANGE
Cash From Operating Activities	182.7M	52.50M	123.1M
Cash From Investing Activities	-16.10M	-10.00M	-149.1M
Cash From Financing Activities	-39.20M	-7.400M	-108.6M
Net Change In Cash	127.4M	35.10M	-134.6M
YoY Change	262.96%	-70.55%	-51.04%
FREE CASH FLOW
Cash From Operating Activities	$182.7M	$52.50M	$123.1M
Capital Expenditures	-$13.20M	-$11.40M	-$11.30M
Free Cash Flow	$195.9M	$63.90M	$134.4M
YoY Change	206.57%	-57.6%	5.49%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2019	dei	Amendment Flag AmendmentFlag	false
CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--08-31
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001144215
CY2018Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1300000	USD
CY2019Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1000000	USD
CY2018Q3	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	0	USD
CY2017	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.52
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.52
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.52
CY2018Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2018Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2019Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2018Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	53667327	shares
CY2019Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	53778155	shares
CY2017	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2017	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	0	acquisition
CY2018	us-gaap	Number Of Reporting Units NumberOfReportingUnits	1	reporting_unit
CY2018Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2018Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	50000000	shares
CY2018Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2018Q3	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2018Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	13676689	shares
CY2019Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	14325197	shares
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-08-31
CY2019	dei	Document Transition Report DocumentTransitionReport	false
CY2019	dei	Entity Registrant Name EntityRegistrantName	ACUITY BRANDS, INC
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity File Number EntityFileNumber	001-16583
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	58-2632672
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	1170 Peachtree Street, N.E.
CY2019	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 2300
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Atlanta
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	GA
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	30309
CY2019	dei	City Area Code CityAreaCode	404
CY2019	dei	Local Phone Number LocalPhoneNumber	853-1400
CY2019	dei	Security12b Title Security12bTitle	Common stock, $0.01 par value per share
CY2019	dei	Trading Symbol TradingSymbol	AYI
CY2019	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2019	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2019	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2019	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2019	dei	Entity Small Business EntitySmallBusiness	false
CY2019	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	dei	Entity Shell Company EntityShellCompany	false
CY2019Q1	dei	Entity Public Float EntityPublicFloat	4550000000	USD
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CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	461000000.0	USD
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CY2018Q3	us-gaap	Inventory Net InventoryNet	411800000	USD
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CY2018Q3	us-gaap	Assets Current AssetsCurrent	1211100000	USD
CY2019Q3	us-gaap	Land Land	22600000	USD
CY2018Q3	us-gaap	Land Land	22900000	USD
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CY2018Q3	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	189100000	USD
CY2019Q3	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	544400000	USD
CY2018Q3	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	516600000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	757700000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	728600000	USD
CY2019Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	480400000	USD
CY2018Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	441900000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	277300000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	286700000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	967300000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	970600000	USD
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CY2019Q3	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	2300000	USD
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CY2019Q3	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	73200000	USD
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CY2019Q3	us-gaap	Liabilities Current LiabilitiesCurrent	596100000	USD
CY2018Q3	us-gaap	Liabilities Current LiabilitiesCurrent	682700000	USD
CY2019Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	347500000	USD
CY2018Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	356400000	USD
CY2019Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	99700000	USD
CY2018Q3	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	64600000	USD
CY2019Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	92700000	USD
CY2018Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	92500000	USD
CY2019Q3	us-gaap	Self Insurance Reserve SelfInsuranceReserve	6800000	USD
CY2018Q3	us-gaap	Self Insurance Reserve SelfInsuranceReserve	7900000	USD
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CY2019Q3	us-gaap	Liabilities Liabilities	1253500000	USD
CY2018Q3	us-gaap	Liabilities Liabilities	1272000000.0	USD
CY2019Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3672700000	USD
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CY2019	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	2193000000.0	USD
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CY2017	us-gaap	Gross Profit GrossProfit	1481100000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	1015000000.0	USD
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CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	462900000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	460800000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	527500000	USD
CY2019	us-gaap	Interest Revenue Expense Net InterestRevenueExpenseNet	-33300000	USD
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CY2019	us-gaap	Net Income Loss NetIncomeLoss	330400000	USD
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CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.32
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CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.46
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39700000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	40900000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	43100000	shares
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.29
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CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.43
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CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	41000000.0	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	43300000	shares
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.52
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.52
CY2017	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.52
CY2019	us-gaap	Net Income Loss NetIncomeLoss	330400000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	349600000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	321700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-11500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-25200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	19000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	25100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-21200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-20700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-36600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	39700000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	293800000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	345600000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	361400000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	330400000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	349600000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	321700000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	88300000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	80300000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	74600000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	29200000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	32300000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	32000000.0	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-900000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-600000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-300000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	9300000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-38200000	USD
CY2017	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-7700000	USD
CY2019	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	5400000	USD
CY2017	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2019	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	0	USD
CY2018	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	0	USD
CY2017	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	7200000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-97700000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	62800000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-2700000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-70800000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	74400000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	32400000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	34000000.0	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-700000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-6000000.0	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-111500000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	52500000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-4600000	USD
CY2019	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-11900000	USD
CY2018	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	19100000	USD
CY2017	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-63500000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-25500000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	2800000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-14700000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	494700000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	351500000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	336600000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	53000000.0	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	43600000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	67300000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	5500000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	2900000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	163200000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	1100000	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2019	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	USD
CY2018	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	USD
CY2017	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	13200000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2900000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1700000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	200000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-53000000.0	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-204000000.0	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-48800000	USD
CY2019	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	86500000	USD
CY2018	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	395400000	USD
CY2017	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2019	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	86500000	USD
CY2018	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	395400000	USD
CY2017	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	400000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	400000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1000000.0	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	81600000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	298400000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	357900000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	600000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	1700000	USD
CY2017	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	3000000.0	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6000000.0	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	8200000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	15200000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	20800000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21400000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	22700000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-108200000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-326700000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-391800000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-1600000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-2800000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1900000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	331900000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-182000000.0	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-102100000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	129100000	USD
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	311100000	USD
CY2016Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	413200000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	461000000.0	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	129100000	USD
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	311100000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	92900000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	126600000	USD
CY2017	us-gaap	Income Taxes Paid IncomeTaxesPaid	173600000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	35600000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	36700000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	33600000	USD
CY2016Q3	us-gaap	Stockholders Equity StockholdersEquity	1659800000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	321700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	39700000	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	16800000	USD
CY2017	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	900000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	22700000	USD
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	2100000	USD
CY2017	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	357900000	USD
CY2017	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	5200000	USD
CY2017Q3	us-gaap	Stockholders Equity StockholdersEquity	1665600000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	349600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4000000.0	USD
CY2018	ayi	Tax Cutsand Jobs Act Reclassificationfrom Aoc Ito Retained Earnings Tax Effect TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect	0	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	23700000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	600000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	21400000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1100000	USD
CY2018	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	298400000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	1716800000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	330400000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-36600000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	600000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	20800000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	23100000	USD
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	81600000	USD
CY2018Q3	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	-13000000.0	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1918900000	USD
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	Segment
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;padding-top:9px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">The preparation of financial statements and related disclosures in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expense during the reporting period. Actual results could differ from those estimates.</span></div>
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	Concentrations of credit risk with respect to receivables, which are typically unsecured, are generally limited due to the wide variety of customers and markets using our lighting and building management solutions as well as their dispersion across many different geographic areas.
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="line-height:120%;padding-top:9px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Certain prior-period amounts have been reclassified to conform to the current year presentation. No material reclassifications occurred during the current period. Refer to the </span><span style="font-family:Arial;font-size:10pt;font-style:italic;">New Accounting Pronouncements</span><span style="font-family:Arial;font-size:10pt;"> footnote for additional information regarding retrospective reclassifications related to accounting standards adopted in the current year.</span></div>
CY2019Q3	us-gaap	Inventory Work In Process And Raw Materials InventoryWorkInProcessAndRawMaterials	179400000	USD
CY2018Q3	us-gaap	Inventory Work In Process And Raw Materials InventoryWorkInProcessAndRawMaterials	196800000	USD
CY2019Q3	us-gaap	Inventory Finished Goods InventoryFinishedGoods	183700000	USD
CY2018Q3	us-gaap	Inventory Finished Goods InventoryFinishedGoods	251800000	USD
CY2019Q3	us-gaap	Inventory Gross InventoryGross	363100000	USD
CY2018Q3	us-gaap	Inventory Gross InventoryGross	448600000	USD
CY2019Q3	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	22300000	USD
CY2018Q3	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	36800000	USD
CY2019Q3	us-gaap	Inventory Net InventoryNet	340800000	USD
CY2018Q3	us-gaap	Inventory Net InventoryNet	411800000	USD
CY2019Q3	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	0	USD
CY2019Q3	us-gaap	Goodwill Goodwill	967300000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	970600000	USD
CY2017Q3	us-gaap	Goodwill Goodwill	900900000	USD
CY2018	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	77000000.0	USD
CY2018	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-7300000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	970600000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	2000000.0	USD
CY2019	us-gaap	Goodwill Purchase Accounting Adjustments GoodwillPurchaseAccountingAdjustments	-200000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-5100000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	967300000	USD
CY2019	us-gaap	Acquired Finite Lived Intangible Assets Weighted Average Useful Life AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife	P17Y
CY2019Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	523900000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	199200000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	526200000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	169200000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	30800000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	28500000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	28000000.0	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	30800000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	28000000.0	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	27000000.0	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	25900000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	25400000	USD
CY2019	us-gaap	Number Of Reporting Units NumberOfReportingUnits	1	reporting_unit
CY2019Q3	us-gaap	Deferred Costs DeferredCosts	15400000	USD
CY2018Q3	us-gaap	Deferred Costs DeferredCosts	12800000	USD
CY2019Q3	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	0	USD
CY2018Q3	us-gaap	Defined Benefit Plan Assets For Plan Benefits Noncurrent DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent	1600000	USD
CY2019Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	2300000	USD
CY2018Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	4400000	USD
CY2019Q3	ayi	Other Long Term Assets OtherLongTermAssets	17700000	USD
CY2018Q3	ayi	Other Long Term Assets OtherLongTermAssets	18800000	USD
CY2019Q3	ayi	Life Insurance Numberof Currentand Former Employees Covered LifeInsuranceNumberofCurrentandFormerEmployeesCovered	66	Employee
CY2019Q3	ayi	Deferred Compensation And Postretirement Defined Benefit Plans Liabilities Noncurrent DeferredCompensationAndPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	41600000	USD
CY2018Q3	ayi	Deferred Compensation And Postretirement Defined Benefit Plans Liabilities Noncurrent DeferredCompensationAndPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	40000000.0	USD
CY2019Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	17600000	USD
CY2018Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	4900000	USD
CY2019Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	5200000	USD
CY2018Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	8200000	USD
CY2019Q3	ayi	Other Long Term Liabilities OtherLongTermLiabilities	110700000	USD
CY2018Q3	ayi	Other Long Term Liabilities OtherLongTermLiabilities	67900000	USD
CY2019	ayi	Deferred Compensation Arrangement With Individual Automatic Contribution Rate DeferredCompensationArrangementWithIndividualAutomaticContributionRate	0.03
CY2019	ayi	Other Shipping And Handling Costs OtherShippingAndHandlingCosts	138400000	USD
CY2018	ayi	Other Shipping And Handling Costs OtherShippingAndHandlingCosts	154900000	USD
CY2017	ayi	Other Shipping And Handling Costs OtherShippingAndHandlingCosts	138300000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	29200000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	32300000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	32000000.0	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6500000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8400000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	11100000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	1600000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	800000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-5200000	USD
CY2019	us-gaap	Depreciation Depreciation	57500000	USD
CY2018	us-gaap	Depreciation Depreciation	51800000	USD
CY2017	us-gaap	Depreciation Depreciation	46600000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	74700000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	63900000	USD
CY2017	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	52000000.0	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	18500000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	20600000	USD
CY2017	us-gaap	Advertising Expense AdvertisingExpense	18600000	USD
CY2019	us-gaap	Interest Expense InterestExpense	36400000	USD
CY2018	us-gaap	Interest Expense InterestExpense	35500000	USD
CY2017	us-gaap	Interest Expense InterestExpense	34100000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	3100000	USD
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	2000000.0	USD
CY2017	us-gaap	Investment Income Interest InvestmentIncomeInterest	1600000	USD
CY2019	us-gaap	Interest Revenue Expense Net InterestRevenueExpenseNet	-33300000	USD
CY2018	us-gaap	Interest Revenue Expense Net InterestRevenueExpenseNet	-33500000	USD
CY2017	us-gaap	Interest Revenue Expense Net InterestRevenueExpenseNet	-32500000	USD
CY2018	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	5400000	USD
CY2017	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	7200000	USD
CY2018	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-2500000	USD
CY2018	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	1500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4000000.0	USD
CY2019	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-42600000	USD
CY2019	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-6000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-36600000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-11500000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-11500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-25200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-25200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	19000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	19000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-40800000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-9700000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-31100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	18400000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	4400000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	14000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	18300000	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	5700000	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	12600000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	3500000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	900000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	2600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	3100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	700000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	2400000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	3100000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	2400000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-4100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-1000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-3100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-6800000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-2000000.0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-4800000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-8900000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-3200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-5700000	USD
CY2019	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIbeforeTax	400000	USD
CY2019	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gain Loss Reclassification Adjustmentfrom Aoci Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainLossReclassificationAdjustmentfromAOCITax	100000	USD
CY2019	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Iafter Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIafterTax	300000	USD
CY2018	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIbeforeTax	0	USD
CY2018	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gain Loss Reclassification Adjustmentfrom Aoci Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainLossReclassificationAdjustmentfromAOCITax	0	USD
CY2018	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Iafter Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIafterTax	0	USD
CY2017	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIbeforeTax	0	USD
CY2017	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gain Loss Reclassification Adjustmentfrom Aoci Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainLossReclassificationAdjustmentfromAOCITax	0	USD
CY2017	ayi	Other Comprehensive Income Loss Defined Benefit Plan Settlement Gains Losses Reclassification Adjustmentfrom Aoc Iafter Tax OtherComprehensiveIncomeLossDefinedBenefitPlanSettlementGainsLossesReclassificationAdjustmentfromAOCIafterTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	32800000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	7700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	25100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-28300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-7100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-21200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-30300000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-9600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-20700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-44300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-7700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-36600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	3100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	7100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	49300000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	9600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	39700000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3672700000	USD
CY2019	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	2193000000.0	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	1015000000.0	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	462900000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94500000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	330400000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.32
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.29
CY2019Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	561000000.0	USD
CY2019Q3	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	79000000.0	USD
CY2019Q3	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	175000000.0	USD
CY2019Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	92700000	USD
CY2019Q3	ayi	Other Long Term Liabilities OtherLongTermLiabilities	110700000	USD
CY2019Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	2295800000	USD
CY2019Q3	us-gaap	Contract With Customer Right To Recover Product ContractWithCustomerRightToRecoverProduct	13900000	USD
CY2018Q3	us-gaap	Contract With Customer Right To Recover Product ContractWithCustomerRightToRecoverProduct	16400000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	4700000	USD
CY2018Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	4800000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	46400000	USD
CY2018Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	35000000.0	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	4100000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3672700000	USD
CY2019Q3	us-gaap	Long Term Debt LongTermDebt	356600000	USD
CY2018Q3	us-gaap	Long Term Debt LongTermDebt	356800000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	350300000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	4400000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	400000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	400000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	300000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	900000	USD
CY2019Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	14300000	shares
CY2018Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	13700000	shares
CY2019Q3	us-gaap	Treasury Stock Value TreasuryStockValue	1200000000	USD
CY2018Q3	us-gaap	Treasury Stock Value TreasuryStockValue	1100000000	USD
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	700000	shares
CY2019Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	50000000	shares
CY2019Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q3	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	330400000	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	349600000	USD
CY2017	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	321700000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39700000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	40900000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	43100000	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2017	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	200000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	39800000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	41000000.0	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	43300000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.32
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	8.54
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.46
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.29
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	8.52
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.43
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	170900000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	16700000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	13500000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	9900000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	7200000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	4600000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	16800000	USD
CY2019	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	22600000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	22300000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	20000000.0	USD
CY2019Q3	us-gaap	Recorded Unconditional Purchase Obligation Due Within One Year RecordedUnconditionalPurchaseObligationDueWithinOneYear	347200000	USD
CY2019Q3	us-gaap	Recorded Unconditional Purchase Obligation Due In Second Year RecordedUnconditionalPurchaseObligationDueInSecondYear	5000000.0	USD
CY2019Q3	us-gaap	Recorded Unconditional Purchase Obligation Due In Third Year RecordedUnconditionalPurchaseObligationDueInThirdYear	5000000.0	USD
CY2019Q3	ayi	Recorded Unconditional Purchase Obligation Dueafter Third Year RecordedUnconditionalPurchaseObligationDueafterThirdYear	0	USD
CY2019	ayi	Standard Product Warranty Period StandardProductWarrantyPeriod	P5Y
CY2018Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	27300000	USD
CY2017Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	22000000.0	USD
CY2016Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	15500000	USD
CY2019	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	18700000	USD
CY2018	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	32400000	USD
CY2017	us-gaap	Standard Product Warranty Accrual Warranties Issued StandardProductWarrantyAccrualWarrantiesIssued	39800000	USD
CY2019	us-gaap	Standard Product Warranty Accrual Payments StandardProductWarrantyAccrualPayments	19700000	USD
CY2018	us-gaap	Standard Product Warranty Accrual Payments StandardProductWarrantyAccrualPayments	27700000	USD
CY2017	us-gaap	Standard Product Warranty Accrual Payments StandardProductWarrantyAccrualPayments	33300000	USD
CY2019	us-gaap	Product Warranty Accrual Additions From Business Acquisition ProductWarrantyAccrualAdditionsFromBusinessAcquisition	0	USD
CY2018	us-gaap	Product Warranty Accrual Additions From Business Acquisition ProductWarrantyAccrualAdditionsFromBusinessAcquisition	600000	USD
CY2017	us-gaap	Product Warranty Accrual Additions From Business Acquisition ProductWarrantyAccrualAdditionsFromBusinessAcquisition	0	USD
CY2019	ayi	Standard Product Warranty Accrual Increase Decreasefor New Accounting Pronouncements StandardProductWarrantyAccrualIncreaseDecreaseforNewAccountingPronouncements	-14800000	USD
CY2018	ayi	Standard Product Warranty Accrual Increase Decreasefor New Accounting Pronouncements StandardProductWarrantyAccrualIncreaseDecreaseforNewAccountingPronouncements	0	USD
CY2017	ayi	Standard Product Warranty Accrual Increase Decreasefor New Accounting Pronouncements StandardProductWarrantyAccrualIncreaseDecreaseforNewAccountingPronouncements	0	USD
CY2019Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	11500000	USD
CY2018Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	27300000	USD
CY2017Q3	us-gaap	Standard Product Warranty Accrual StandardProductWarrantyAccrual	22000000.0	USD
CY2019	us-gaap	Restructuring Charges RestructuringCharges	1800000	USD
CY2018	us-gaap	Restructuring Charges RestructuringCharges	5600000	USD
CY2019Q3	us-gaap	Restructuring Reserve RestructuringReserve	1900000	USD
CY2018Q3	us-gaap	Restructuring Reserve RestructuringReserve	10100000	USD
CY2019	us-gaap	Payments For Restructuring PaymentsForRestructuring	7700000	USD
CY2019Q3	us-gaap	Restructuring Reserve RestructuringReserve	1900000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	60300000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	88900000	USD
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CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-204000000.0	USD
CY2018	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	395400000	USD
CY2018	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	395400000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	400000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	1700000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	298400000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	8200000	USD
CY2018	ayi	Intercompany Dividends IntercompanyDividends	0	USD
CY2018	ayi	Intercompany Capital IntercompanyCapital	0	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21400000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-326700000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-2800000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-182000000.0	USD
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	311100000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	129100000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	336600000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	67300000	USD
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	5500000	USD
CY2017	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	13200000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	200000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-48800000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1000000.0	USD
CY2017	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	3000000.0	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	357900000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	15200000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	22700000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-391800000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1900000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-102100000	USD
CY2016Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	413200000	USD
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	311100000	USD
CY2018Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	932600000	USD
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	854400000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	947600000	USD
CY2019Q2	us-gaap	Gross Profit GrossProfit	383600000	USD
CY2019Q3	us-gaap	Gross Profit GrossProfit	394700000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	79600000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	66300000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	88400000	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	938100000	USD
CY2018Q4	us-gaap	Gross Profit GrossProfit	367500000	USD
CY2019Q1	us-gaap	Gross Profit GrossProfit	333900000	USD
CY2018Q2	us-gaap	Gross Profit GrossProfit	389100000	USD
CY2018Q3	us-gaap	Gross Profit GrossProfit	411900000	USD
CY2017Q4	us-gaap	Net Income Loss NetIncomeLoss	71500000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	96900000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	96100000	USD
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.99
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.68
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.23
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.43
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.98
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.67
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.22
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.42
CY2017Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	842800000	USD
CY2018Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	832100000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	944000000.0	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1061200000	USD
CY2017Q4	us-gaap	Gross Profit GrossProfit	349900000	USD
CY2018Q1	us-gaap	Gross Profit GrossProfit	334500000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	73000000.0	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	108200000	USD
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.71
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.34
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.81
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.71
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.70
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.33
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.80
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.70

Files In Submission

Name	View Source	Status
0001144215-19-000114-index-headers.html	Edgar Link	pending
0001144215-19-000114-index.html	Edgar Link	pending
0001144215-19-000114.txt	Edgar Link	pending
0001144215-19-000114-xbrl.zip	Edgar Link	pending
ayi-20190831.xsd	Edgar Link	pending
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ayi-20190831x10k_htm.xml	Edgar Link	completed
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ayi-20190831_cal.xml	Edgar Link	unprocessable
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$AYI
ACUITY BRANDS INC Stock $ayi

2019 Q3 Form 10-K Financial Statement

#000114421519000114 Filed on October 29, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AYI ACUITY BRANDS INC Stock $ayi

2019 Q3 Form 10-K Financial Statement

#000114421519000114 Filed on October 29, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AYI
ACUITY BRANDS INC Stock $ayi