$ATI
ATI INC Stock $ati

$ati Overview Financials Valuation SEC Filings Company Website

2019 Q3 Form 10-Q Financial Statement

#000101896319000024 Filed on November 01, 2019

Income Statement

Concept	2019 Q3	2019 Q1	2018 Q4
Revenue	$1.019B	$1.005B	$1.038B
YoY Change	-0.15%	2.64%	14.07%
Cost Of Revenue	$859.0M	$873.7M	$890.3M
YoY Change	-0.09%	5.21%	16.03%
Gross Profit	$159.7M	$131.1M	$147.6M
YoY Change	-0.44%	-11.78%	3.51%
Gross Profit Margin	15.68%	13.05%	14.22%
Selling, General & Admin	$65.20M	$68.00M	$72.90M
YoY Change	-0.46%	1.34%	20.5%
% of Gross Profit	40.83%	51.87%	49.39%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$37.00M	$38.70M	$39.30M
YoY Change	-3.65%	-2.76%	-2.0%
% of Gross Profit	23.17%	29.52%	26.63%
Operating Expenses	$65.20M	$68.00M	$72.90M
YoY Change	-0.46%	1.34%	20.5%
Operating Profit	$94.50M	$63.10M	$74.70M
YoY Change	-0.42%	-22.58%	-9.01%
Interest Expense	-$26.60M	-$24.80M	-$25.20M
YoY Change	7.26%	-2.75%	-20.25%
% of Operating Profit	-28.15%	-39.3%	-33.73%
Other Income/Expense, Net	$67.20M	-$2.900M	-$10.30M
YoY Change	8300.0%	-116.29%	-21.37%
Pretax Income	$119.0M	$17.10M	$39.20M
YoY Change	90.4%	-73.89%	9700.0%
Income Tax	$3.700M	$800.0K	-$11.70M
% Of Pretax Income	3.11%	4.68%	-29.85%
Net Earnings	$111.0M	$15.00M	$41.10M
YoY Change	119.8%	-74.14%	2317.65%
Net Earnings / Revenue	10.9%	1.49%	3.96%
Basic Earnings Per Share	$0.88	$0.12	$0.33
Diluted Earnings Per Share	$0.78	$0.12	$0.30
COMMON SHARES
Basic Shares Outstanding	126.1M shares	125.8M shares	125.7M shares
Diluted Shares Outstanding	146.7M shares	126.1M shares

Balance Sheet

Concept	2019 Q3	2019 Q1	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$511.3M	$217.0M	$382.0M
YoY Change	233.09%	97.45%	169.77%
Cash & Equivalents	$511.3M	$217.0M	$382.0M
Short-Term Investments
Other Short-Term Assets	$108.1M	$92.70M	$74.60M
YoY Change	21.19%	7.67%	41.56%
Inventory	$1.169B	$1.254B	$1.211B
Prepaid Expenses
Receivables	$596.7M	$565.1M	$527.8M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$2.422B	$2.178B	$2.247B
YoY Change	14.13%	6.15%	17.28%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.408B	$2.471B	$2.475B
YoY Change	-2.63%	-0.8%	-0.83%
Goodwill	$523.8M	$536.8M	$534.7M
YoY Change	-2.35%	0.49%	0.62%
Intangibles
YoY Change
Long-Term Investments	$0.00	$0.00	$0.00
YoY Change
Other Assets	$275.2M	$305.6M	$245.4M
YoY Change	6.83%	18.82%	1.15%
Total Long-Term Assets	$3.207B	$3.313B	$3.255B
YoY Change	-1.84%	0.45%	-0.45%
TOTAL ASSETS
Total Short-Term Assets	$2.422B	$2.178B	$2.247B
Total Long-Term Assets	$3.207B	$3.313B	$3.255B
Total Assets	$5.629B	$5.491B	$5.502B
YoY Change	4.45%	2.64%	6.1%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$415.8M	$455.3M	$498.8M
YoY Change	-0.07%	7.21%	18.73%
Accrued Expenses	$238.3M	$220.4M	$260.1M
YoY Change	4.2%	7.36%	-7.9%
Deferred Revenue	$97.10M	$77.90M	$71.40M
YoY Change	40.32%	11.76%	2.44%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$12.10M	$6.400M	$6.600M
YoY Change	-27.11%	-89.95%	-34.65%
Total Short-Term Liabilities	$763.3M	$760.0M	$836.9M
YoY Change	4.48%	0.01%	17.44%
LONG-TERM LIABILITIES
Long-Term Debt	$1.542B	$1.536B	$1.536B
YoY Change	0.42%	0.06%	0.32%
Other Long-Term Liabilities	$124.9M	$123.1M	$89.40M
YoY Change	87.26%	96.96%	22.13%
Total Long-Term Liabilities	$124.9M	$123.1M	$89.40M
YoY Change	87.26%	96.96%	22.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$763.3M	$760.0M	$836.9M
Total Long-Term Liabilities	$124.9M	$123.1M	$89.40M
Total Liabilities	$3.349B	$3.444B	$3.510B
YoY Change	1.31%	1.7%	5.07%
SHAREHOLDERS EQUITY
Retained Earnings	$1.623B	$1.437B	$1.427B
YoY Change	17.52%	14.25%	20.5%
Common Stock	$1.625B	$1.612B	$1.628B
YoY Change	0.22%	0.01%	1.19%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$18.20M	$19.70M	$30.60M
YoY Change	-40.52%	-37.85%	17.24%
Treasury Stock Shares	609.8K shares	660.3K shares	1.011M shares
Shareholders Equity	$2.168B	$1.934B	$1.886B
YoY Change
Total Liabilities & Shareholders Equity	$5.629B	$5.491B	$5.502B
YoY Change	4.45%	2.64%	6.1%

Cashflow Statement

Concept	2019 Q3	2019 Q1	2018 Q4
OPERATING ACTIVITIES
Net Income	$111.0M	$15.00M	$41.10M
YoY Change	119.8%	-74.14%	2317.65%
Depreciation, Depletion And Amortization	$37.00M	$38.70M	$39.30M
YoY Change	-3.65%	-2.76%	-2.0%
Cash From Operating Activities	$94.40M	-$130.0M	$276.2M
YoY Change	15.69%	176.01%	262.47%
INVESTING ACTIVITIES
Capital Expenditures	-$46.90M	-$23.60M	-$37.90M
YoY Change	52.77%	-43.27%	1.34%
Acquisitions
YoY Change
Other Investing Activities	$184.9M	$100.0K	$1.900M
YoY Change	-2250.0%	-200.0%	-2000.0%
Cash From Investing Activities	$138.0M	-$23.60M	-$36.00M
YoY Change	-451.15%	-43.13%	-4.0%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-2.300M	-$11.40M	-11.70M
YoY Change	-79.46%	-120.04%	-46.82%
NET CHANGE
Cash From Operating Activities	94.40M	-$130.0M	276.2M
Cash From Investing Activities	138.0M	-$23.60M	-36.00M
Cash From Financing Activities	-2.300M	-$11.40M	-11.70M
Net Change In Cash	230.1M	-$165.0M	228.5M
YoY Change	639.87%	420.5%	1268.26%
FREE CASH FLOW
Cash From Operating Activities	$94.40M	-$130.0M	$276.2M
Capital Expenditures	-$46.90M	-$23.60M	-$37.90M
Free Cash Flow	$141.3M	-$106.4M	$314.1M
YoY Change	25.82%	1834.55%	176.5%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
	dei	Entity Central Index Key EntityCentralIndexKey	0001018963
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Amendment Flag AmendmentFlag	false
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.10
CY2019Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.10
CY2018Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2019Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2018Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	126695171	shares
CY2019Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	126695171	shares
CY2018Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	125684396	shares
CY2019Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	126085348	shares
CY2018Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.10
CY2019Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.10
CY2018Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	50000000	shares
CY2019Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	50000000	shares
CY2018Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2018Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	1010775	shares
	dei	Entity File Number EntityFileNumber	1-12001
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	15222-5479
	dei	Entity Registrant Name EntityRegistrantName	ALLEGHENY TECHNOLOGIES INCORPORATED
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	25-1792394
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1000 Six PPG Place
	dei	Entity Address City Or Town EntityAddressCityOrTown	Pittsburgh,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	PA
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	609823	shares
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	City Area Code CityAreaCode	412
	dei	Local Phone Number LocalPhoneNumber	394-2800
	dei	Security12b Title Security12bTitle	Common stock, par value $0.10
	dei	Trading Symbol TradingSymbol	ATI
	dei	Security Exchange Name SecurityExchangeName	NYSE
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Shell Company EntityShellCompany	false
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	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-16400000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	14300000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	-10800000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	19100000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	2400000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	800000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	2600000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	-600000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	10300000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	0	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	13500000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-13400000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	19700000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-7900000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-21900000	USD
CY2019Q3	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	-700000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	69400000	USD
CY2018Q3	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	-700000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18400000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-8700000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-19200000	USD
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	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	-1900000	USD
	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	-1900000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-21200000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-18500000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-63500000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-55600000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	31300000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	133700000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	46900000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	279500000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	223000000.0	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-300000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-3900000	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	6000000.0	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	5200000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	134000000.0	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	50800000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	273500000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	217800000	USD
	us-gaap	Profit Loss ProfitLoss	210100000	USD
	us-gaap	Profit Loss ProfitLoss	191700000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	114600000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	117100000	USD
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	4100000	USD
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	2800000	USD
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	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	15900000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	90600000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	500000	USD
	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	-1800000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	43000000.0	USD
	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	-75200000	USD
	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	0	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-12200000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	137200000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	92500000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	4200000	USD
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	71000000.0	USD
	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-86000000.0	USD
	us-gaap	Increase Decrease In Pension And Postretirement Obligations IncreaseDecreaseInPensionAndPostretirementObligations	-10100000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	4700000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	12700000	USD
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	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	98100000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	101300000	USD
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	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	5300000	USD
	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	4600000	USD
	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	5100000	USD
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	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	9900000	USD
	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	6500000	USD
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	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	11900000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	382000000.0	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	141600000	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	511300000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	153500000	USD
CY2018Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2041900000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	55600000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-8700000	USD
CY2018Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	10000000.0	USD
CY2018Q3	ati	Employee Stock Plans EmployeeStockPlans	-4400000	USD
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2083200000	USD
CY2019Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2138600000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	115300000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18400000	USD
CY2019Q3	ati	Employee Stock Plans EmployeeStockPlans	-7600000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2279900000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1844500000	USD
	us-gaap	Profit Loss ProfitLoss	191700000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	31300000	USD
	us-gaap	Cumulative Effect On Retained Earnings Net Of Tax1 CumulativeEffectOnRetainedEarningsNetOfTax1	15500000	USD
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	10000000.0	USD
	us-gaap	Noncontrolling Interest Increase From Sale Of Parent Equity Interest NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest	2700000	USD
	ati	Employee Stock Plans EmployeeStockPlans	-7500000	USD
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2083200000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1991600000	USD
	us-gaap	Profit Loss ProfitLoss	210100000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	69400000	USD
	ati	Employee Stock Plans EmployeeStockPlans	-8800000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2279900000	USD
	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<div style="line-height:120%;text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-weight:bold;">Pending Accounting Pronouncements</span></div><div style="line-height:120%;text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div><div style="line-height:120%;text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In August 2018, the FASB issued new disclosure guidance on fair value measurement. This new guidance modifies the disclosure requirements on fair value measurements, including removal and modifications of various current disclosures as well as some additional disclosure requirements for Level 3 fair value measurements. Some of these disclosure changes must be applied prospectively while others must be applied retrospectively. This guidance is required to be adopted by the Company beginning in fiscal year 2020 with early adoption permitted. The Company does not plan to early adopt this guidance. The adoption of these changes is not expected to have an impact on the Company’s consolidated financial statements other than disclosures. </span></div><div style="line-height:120%;text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div><div style="line-height:120%;text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">In June 2016, the FASB added a new impairment model (known as the current expected credit loss (CECL) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to trade receivables, other receivables, and most debt instruments. The CECL model does not have a minimum threshold for recognition of impairment losses, and entities will need to measure expected credit losses on assets that have a low risk of loss. This guidance is required to be adopted by the Company beginning in fiscal year 2020. Management is currently evaluating the potential impact of these changes on the Company’s consolidated financial statements and does not expect these changes to have a significant impact on the Company’s consolidated financial statements.</span></div>
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1018700000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1020200000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3103900000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3008700000	USD
	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	segment
	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	segment
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1018700000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1020200000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3103900000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3008700000	USD
CY2019Q3	ati	Revenuefrom Contractwith Customer Excluding Assessed Tax Percentageof Revenue RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue	1
CY2018Q3	ati	Revenuefrom Contractwith Customer Excluding Assessed Tax Percentageof Revenue RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue	1
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	ati	Revenuefrom Contractwith Customer Excluding Assessed Tax Percentageof Revenue RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue	1
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2340000000	USD
CY2018Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2170000000	USD
CY2019Q3	ati	Revenue Remaining Performance Obligation Current RevenueRemainingPerformanceObligationCurrent	0.75	USD
CY2019Q3	ati	Accountsreceivablewithcustomers Accountsreceivablewithcustomers	601700000	USD
CY2018Q4	ati	Accountsreceivablewithcustomers Accountsreceivablewithcustomers	533800000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	6000000.0	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	5900000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	300000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	700000	USD
	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	1300000	USD
	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	400000	USD
CY2019Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	5000000.0	USD
	ati	Contractwith Customer Asset Current Period Increase ContractwithCustomerAssetCurrentPeriodIncrease	57000000.0	USD
	ati	Contractwith Customer Asset Noncurrent Reclassifiedto Receivable ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable	0	USD
CY2018Q3	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	6200000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	51200000	USD
CY2018Q1	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	36500000	USD
	ati	Contractwith Customer Asset Current Period Increase ContractwithCustomerAssetCurrentPeriodIncrease	66200000	USD
	ati	Contractwith Customer Asset Current Reclassifiedto Receivable ContractwithCustomerAssetCurrentReclassifiedtoReceivable	63100000	USD
	ati	Contractwith Customer Asset Current Reclassifiedto Receivable ContractwithCustomerAssetCurrentReclassifiedtoReceivable	67900000	USD
	ati	Contractwith Customer Asset Current Impairment ContractwithCustomerAssetCurrentImpairment	0	USD
	ati	Contractwith Customer Asset Current Impairment ContractwithCustomerAssetCurrentImpairment	0	USD
	ati	Contractwith Customer Asset Current Reclassification ContractwithCustomerAssetCurrentReclassification	0	USD
	ati	Contractwith Customer Asset Current Reclassification ContractwithCustomerAssetCurrentReclassification	-16800000	USD
	ati	Contractwithcustomer Asset Current Divestiture ContractwithcustomerAssetCurrentDivestiture	7300000	USD
	ati	Contractwithcustomer Asset Current Divestiture ContractwithcustomerAssetCurrentDivestiture	0	USD
CY2019Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	37800000	USD
CY2018Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	51600000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	100000	USD
CY2018Q1	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	16900000	USD
	ati	Contractwith Customer Asset Nocurrent Period Increase ContractwithCustomerAssetNocurrentPeriodIncrease	0	USD
	ati	Contractwith Customer Asset Nocurrent Period Increase ContractwithCustomerAssetNocurrentPeriodIncrease	0	USD
	ati	Contractwith Customer Asset Noncurrent Reclassifiedto Receivable ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable	0	USD
	ati	Contractwith Customer Asset Noncurrent Impairment ContractwithCustomerAssetNoncurrentImpairment	0	USD
	ati	Contractwith Customer Asset Noncurrent Impairment ContractwithCustomerAssetNoncurrentImpairment	0	USD
	ati	Contractwith Customer Asset Noncurrent Reclassification ContractwithCustomerAssetNoncurrentReclassification	0	USD
	ati	Contractwith Customer Asset Noncurrent Reclassification ContractwithCustomerAssetNoncurrentReclassification	16800000	USD
CY2019Q3	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	100000	USD
CY2018Q3	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	100000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	71400000	USD
CY2018Q1	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	69700000	USD
	ati	Contractwith Customer Liability Current Period Increase ContractwithCustomerLiabilityCurrentPeriodIncrease	104200000	USD
	ati	Contractwith Customer Liability Current Period Increase ContractwithCustomerLiabilityCurrentPeriodIncrease	46900000	USD
	ati	Contractwith Customer Liability Current Reclassifiedto Revenue ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue	-43900000	USD
	ati	Contractwith Customer Liability Current Reclassifiedto Revenue ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue	-40100000	USD
	ati	Contractwith Customer Liability Current Revenue Recognized ContractwithCustomerLiabilityCurrentRevenueRecognized	-34800000	USD
	ati	Contractwith Customer Liability Current Revenue Recognized ContractwithCustomerLiabilityCurrentRevenueRecognized	-23600000	USD
	ati	Contractwith Customer Liability Current Other ContractwithCustomerLiabilityCurrentOther	200000	USD
	ati	Contractwith Customer Liability Current Other ContractwithCustomerLiabilityCurrentOther	1700000	USD
	ati	Contractwith Customer Liability Current Reclassification ContractwithCustomerLiabilityCurrentReclassification	0	USD
	ati	Contractwith Customer Liability Current Reclassification ContractwithCustomerLiabilityCurrentReclassification	-14600000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	97100000	USD
CY2018Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	69200000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	7300000	USD
CY2018Q1	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	22200000	USD
	ati	Contractwith Customer Liability Noncurrent Period Increase ContractwithCustomerLiabilityNoncurrentPeriodIncrease	800000	USD
	ati	Contractwith Customer Liability Noncurrent Period Increase ContractwithCustomerLiabilityNoncurrentPeriodIncrease	500000	USD
	ati	Contractwith Customer Liability Noncurrent Reclassifiedto Revenue ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue	-800000	USD
	ati	Contractwith Customer Liability Noncurrent Reclassifiedto Revenue ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue	-800000	USD
	ati	Contractwith Customer Liability Noncurrent Revenue Recognized ContractwithCustomerLiabilityNoncurrentRevenueRecognized	0	USD
	ati	Contractwith Customer Liability Noncurrent Revenue Recognized ContractwithCustomerLiabilityNoncurrentRevenueRecognized	0	USD
	ati	Contractwith Customer Liability Noncurrent Other ContractwithCustomerLiabilityNoncurrentOther	0	USD
	ati	Contractwith Customer Liability Noncurrent Other ContractwithCustomerLiabilityNoncurrentOther	0	USD
	ati	Contractwith Customer Liability Noncurrent Reclassification ContractwithCustomerLiabilityNoncurrentReclassification	0	USD
	ati	Contractwith Customer Liability Noncurrent Reclassification ContractwithCustomerLiabilityNoncurrentReclassification	14600000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	7300000	USD
CY2018Q3	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	7300000	USD
CY2019Q3	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	5100000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	5200000	USD
CY2019Q3	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	400000	USD
	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1000000.0	USD
CY2018Q3	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	300000	USD
	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	900000	USD
CY2019Q3	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	199600000	USD
CY2018Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	191500000	USD
CY2019Q3	us-gaap	Inventory Work In Process InventoryWorkInProcess	863500000	USD
CY2018Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	914100000	USD
CY2019Q3	us-gaap	Inventory Finished Goods InventoryFinishedGoods	180900000	USD
CY2018Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	191100000	USD
CY2019Q3	us-gaap	Inventory Gross InventoryGross	1244000000.0	USD
CY2018Q4	us-gaap	Inventory Gross InventoryGross	1296700000	USD
CY2019Q3	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	-6700000	USD
CY2018Q4	us-gaap	Inventory Lifo Reserve InventoryLIFOReserve	-2900000	USD
CY2019Q3	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	82200000	USD
CY2018Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	88500000	USD
CY2019Q3	us-gaap	Inventory Net InventoryNet	1168500000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	1211100000	USD
	us-gaap	Inventory Lifo Reserve Period Charge InventoryLIFOReservePeriodCharge	1400000	USD
	us-gaap	Inventory Lifo Reserve Period Charge InventoryLIFOReservePeriodCharge	29500000	USD
	ati	Inventory Net Realizable Value Reserve Period Charge InventoryNetRealizableValueReservePeriodCharge	-1300000	USD
	ati	Inventory Net Realizable Value Reserve Period Charge InventoryNetRealizableValueReservePeriodCharge	-29500000	USD
	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	100000	USD
	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	0	USD
CY2019Q3	us-gaap	Land Land	34400000	USD
CY2018Q4	us-gaap	Land Land	31500000	USD
CY2019Q3	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	821300000	USD
CY2018Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	851700000	USD
CY2019Q3	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	3612100000	USD
CY2018Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	3622700000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	4467800000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	4505900000	USD
CY2019Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	2060300000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	2030900000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2407500000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2475000000.0	USD
CY2019Q3	us-gaap	Construction In Progress Gross ConstructionInProgressGross	123900000	USD
CY2019Q2	ati	Number Of Facilities Sold NumberOfFacilitiesSold	2	facility
CY2019Q2	ati	Number Of Facilities Sold NumberOfFacilitiesSold	2	facility
	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	15900000	USD
CY2019Q3	ati	Rent Royalty And Other Income RentRoyaltyAndOtherIncome	1400000	USD
CY2018Q3	ati	Rent Royalty And Other Income RentRoyaltyAndOtherIncome	600000	USD
	ati	Rent Royalty And Other Income RentRoyaltyAndOtherIncome	2800000	USD
	ati	Rent Royalty And Other Income RentRoyaltyAndOtherIncome	2300000	USD
CY2019Q3	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	62300000	USD
CY2018Q3	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	100000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	90600000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	500000	USD
CY2019Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-2400000	USD
CY2018Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	200000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-8700000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	2500000	USD
CY2019Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	5800000	USD
CY2018Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-1900000	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2019Q3	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
CY2018Q3	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	15900000	USD
CY2019Q3	ati	Other Other Nonoperating Income Expense OtherOtherNonoperatingIncomeExpense	100000	USD
CY2018Q3	ati	Other Other Nonoperating Income Expense OtherOtherNonoperatingIncomeExpense	-100000	USD
	ati	Other Other Nonoperating Income Expense OtherOtherNonoperatingIncomeExpense	100000	USD
	ati	Other Other Nonoperating Income Expense OtherOtherNonoperatingIncomeExpense	1200000	USD
CY2019Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	67200000	USD
CY2018Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	800000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	82900000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	USD
CY2019Q3	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	62400000	USD
	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	91700000	USD
CY2019Q3	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	8300000	USD
CY2018Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	10400000	USD
CY2019Q3	ati	Total Debt TotalDebt	1553800000	USD
CY2018Q4	ati	Total Debt TotalDebt	1542100000	USD
CY2019Q3	us-gaap	Debt Current DebtCurrent	12100000	USD
CY2018Q4	us-gaap	Debt Current DebtCurrent	6600000	USD
CY2019Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	1541700000	USD
CY2018Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	1535500000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	51700000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	55600000	USD
CY2019Q1	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	12500000	USD
CY2019Q4	ati	Progress Payments Made On Behalf Of Company Scheduled To Be Paid ProgressPaymentsMadeOnBehalfOfCompanyScheduledToBePaid	9500000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	15400000	USD
CY2019Q1	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	43100000	USD
CY2019Q3	ati	Progress Payments Made On Behalf Of Company Paid ProgressPaymentsMadeOnBehalfOfCompanyPaid	1700000	USD
CY2019Q3	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	500000	USD
	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	1000000.0	USD
CY2019Q3	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	100000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	300000	USD
CY2019Q3	us-gaap	Operating Lease Cost OperatingLeaseCost	5000000.0	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	15400000	USD
CY2019Q3	us-gaap	Short Term Lease Cost ShortTermLeaseCost	700000	USD
	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2400000	USD
CY2019Q3	us-gaap	Variable Lease Cost VariableLeaseCost	200000	USD
	us-gaap	Variable Lease Cost VariableLeaseCost	600000	USD
CY2019Q3	us-gaap	Sublease Income SubleaseIncome	0	USD
	us-gaap	Sublease Income SubleaseIncome	0	USD
CY2019Q3	us-gaap	Lease Cost LeaseCost	6500000	USD
	us-gaap	Lease Cost LeaseCost	19700000	USD
CY2019Q3	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	100000	USD
	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	300000	USD
CY2019Q3	us-gaap	Operating Lease Payments OperatingLeasePayments	5000000.0	USD
CY2019Q3	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	700000	USD
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1500000	USD
CY2019Q3	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	6700000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	12600000	USD
CY2019Q3	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	2800000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	20300000	USD
CY2019Q3	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P4Y
CY2019Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y
CY2019Q3	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.053
CY2019Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.071
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	5100000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	18500000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	16900000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	15300000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	66300000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	13200000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	9000000.0	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	18900000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	81600000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	3900000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	3500000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2400000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	500000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	15400000	USD
CY2019Q3	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	1600000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Remainder Of Fiscal Year FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear	1000000.0	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	4100000	USD
CY2019Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	13800000	USD
	ati	Percentage Of Raw Material Usage Hedged PercentageOfRawMaterialUsageHedged	0.09
	ati	Percentage Of Forecasted Natural Gas Usage Hedgedfor Year1 PercentageOfForecastedNaturalGasUsageHedgedforYear1	0.70
	ati	Percentage Of Forecasted Natural Gas Usage Hedgedfor Year2 PercentageOfForecastedNaturalGasUsageHedgedforYear2	0.70
	ati	Percentage Of Forecasted Natural Gas Usage Hedgedfor Year3 PercentageOfForecastedNaturalGasUsageHedgedforYear3	0.50
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	17500000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	3400000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	5100000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	10400000	USD
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	11500000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3700000	USD
CY2019Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.031
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6900000	USD
CY2018Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.110
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10300000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.047
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16800000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.081
	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	segment
CY2019Q3	ati	Segment Operating Profit Loss SegmentOperatingProfitLoss	99200000	USD
CY2018Q3	ati	Segment Operating Profit Loss SegmentOperatingProfitLoss	105500000	USD
	ati	Segment Operating Profit Loss SegmentOperatingProfitLoss	275400000	USD
	ati	Segment Operating Profit Loss SegmentOperatingProfitLoss	325900000	USD
CY2019Q3	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	0	USD
CY2018Q3	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	0	USD
	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	100000	USD
	ati	Lifo Provision Benefitand Changein Debit Lifonr Vreservenet LifoProvisionBenefitandChangeinDebitLIFONRVreservenet	0	USD
CY2019Q3	ati	Corporate Expenses CorporateExpenses	16000000.0	USD
CY2018Q3	ati	Corporate Expenses CorporateExpenses	14800000	USD
	ati	Corporate Expenses CorporateExpenses	50600000	USD
	ati	Corporate Expenses CorporateExpenses	40900000	USD
CY2019Q3	ati	Other Expense OtherExpense	8200000	USD
CY2018Q3	ati	Other Expense OtherExpense	3400000	USD
	ati	Other Expense OtherExpense	19200000	USD
	ati	Other Expense OtherExpense	16600000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	119000000.0	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	62500000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	220400000	USD
CY2019Q3	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
CY2018Q3	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	15900000	USD
CY2019Q3	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	68200000	USD
CY2018Q3	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	0	USD
	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	89800000	USD
	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	0	USD
CY2019Q3	ati	Interest Expense Net InterestExpenseNet	24200000	USD
CY2018Q3	ati	Interest Expense Net InterestExpenseNet	24800000	USD
	ati	Interest Expense Net InterestExpenseNet	74900000	USD
	ati	Interest Expense Net InterestExpenseNet	75800000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	208500000	USD
CY2019Q3	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	68200000	USD
CY2019Q3	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	62400000	USD
	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	89800000	USD
	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	91700000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	111000000.0	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	50500000	USD
	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	201100000	USD
	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	181300000	USD
CY2019Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	3200000	USD
CY2018Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	3200000	USD
	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	9700000	USD
	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	9600000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	114200000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	53700000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	210800000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	190900000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	125900000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	125200000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	125700000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	125100000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	900000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	900000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	800000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	700000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	19900000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	19900000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	19900000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	19900000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	146700000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	146000000.0	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	146400000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	145700000	shares
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.88
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.40
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.60
	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.45
CY2019Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.78
CY2018Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.37
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.44
	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.31
CY2019Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	511300000	USD
CY2019Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	596700000	USD
CY2019Q3	us-gaap	Notes Receivable Related Parties Current NotesReceivableRelatedPartiesCurrent	0	USD
CY2019Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	37800000	USD
CY2019Q3	us-gaap	Inventory Net InventoryNet	1168500000	USD
CY2019Q3	us-gaap	Other Assets Current OtherAssetsCurrent	108100000	USD
CY2019Q3	us-gaap	Assets Current AssetsCurrent	2422400000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2407500000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	523800000	USD
CY2019Q3	us-gaap	Notes Receivable Related Parties Noncurrent NotesReceivableRelatedPartiesNoncurrent	0	USD
CY2019Q3	us-gaap	Equity Method Investments EquityMethodInvestments	0	USD
CY2019Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	275200000	USD
CY2019Q3	us-gaap	Assets Assets	5628900000	USD
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CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3700000	USD
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	us-gaap	Operating Income Loss OperatingIncomeLoss	267600000	USD
	ati	Nonoperatingretirementbenefitexpense Nonoperatingretirementbenefitexpense	55200000	USD
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	us-gaap	Net Income Loss NetIncomeLoss	201100000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	273500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-10000000.0	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	98100000	USD
	ati	Proceeds Paymentsfrom Intercompany Activites Investing Activities ProceedsPaymentsfromIntercompanyActivitesInvestingActivities	0	USD
	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	-155900000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	91800000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	200000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	149400000	USD
	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	5300000	USD
	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	5100000	USD
	ati	Netreceiptspaymentsonintercompanyactivity Netreceiptspaymentsonintercompanyactivity	0	USD
	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	9900000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-10100000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	129300000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	382000000.0	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2475000000.0	USD
CY2018Q4	us-gaap	Goodwill Goodwill	534700000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	50500000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	50800000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3008700000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	527800000	USD
CY2018Q4	us-gaap	Notes Receivable Related Parties Current NotesReceivableRelatedPartiesCurrent	0	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	51200000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	1211100000	USD
CY2018Q4	us-gaap	Other Assets Current OtherAssetsCurrent	74600000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	2246700000	USD
CY2018Q4	us-gaap	Notes Receivable Related Parties Noncurrent NotesReceivableRelatedPartiesNoncurrent	0	USD
CY2018Q4	us-gaap	Equity Method Investments EquityMethodInvestments	0	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	245400000	USD
CY2018Q4	us-gaap	Assets Assets	5501800000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	498800000	USD
CY2018Q4	us-gaap	Notes Payable Related Parties Classified Current NotesPayableRelatedPartiesClassifiedCurrent	0	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	71400000	USD
CY2018Q4	us-gaap	Debt Current DebtCurrent	6600000	USD
CY2018Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	260100000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	836900000	USD
CY2018Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	1535500000	USD
CY2018Q4	us-gaap	Notes Payable Related Parties Noncurrent NotesPayableRelatedPartiesNoncurrent	0	USD
CY2018Q4	us-gaap	Other Postretirement Defined Benefit Plan Liabilities Noncurrent OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent	318400000	USD
CY2018Q4	us-gaap	Defined Benefit Pension Plan Liabilities Noncurrent DefinedBenefitPensionPlanLiabilitiesNoncurrent	730000000.0	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	12900000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	76500000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	3510200000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1991600000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	5501800000	USD
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CY2018Q3	us-gaap	Gross Profit GrossProfit	160400000	USD
CY2018Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	65500000	USD
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CY2018Q3	ati	Nonoperatingretirementbenefitexpense Nonoperatingretirementbenefitexpense	8400000	USD
CY2018Q3	ati	Interest Expense Net InterestExpenseNet	24800000	USD
CY2018Q3	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	800000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	62500000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	6900000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	55600000	USD
CY2018Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5100000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	2526000000.0	USD
	us-gaap	Gross Profit GrossProfit	482700000	USD
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	ati	Nonoperatingretirementbenefitexpense Nonoperatingretirementbenefitexpense	25500000	USD
	ati	Interest Expense Net InterestExpenseNet	75800000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	USD
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	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16800000	USD
	us-gaap	Profit Loss ProfitLoss	191700000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	10400000	USD
	us-gaap	Net Income Loss NetIncomeLoss	181300000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	217800000	USD
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	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	0	USD
	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	10000000.0	USD
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	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	4400000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	11900000	USD
CY2019Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1084400000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-1100000	USD
CY2019Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-24100000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	23000000.0	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1061400000	USD
CY2019Q2	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	12700000	USD
CY2019Q3	ati	Other Comprehensive Income Loss Before Reclassification Adjustments Net Of Tax Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest	-4600000	USD
CY2019Q3	ati	Reclassificationfrom Accumulated Other Comprehensive Income Loss Current Period Netof Tax Attributableto Noncontrolling Interest ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-4600000	USD
CY2019Q3	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	8100000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1133800000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	3500000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-68900000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	72400000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1061400000	USD
CY2018Q4	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	11100000	USD
	ati	Other Comprehensive Income Loss Before Reclassification Adjustments Net Of Tax Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest	-3000000.0	USD
	ati	Reclassificationfrom Accumulated Other Comprehensive Income Loss Current Period Netof Tax Attributableto Noncontrolling Interest ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest	0	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-3000000.0	USD
CY2019Q3	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	8100000	USD
CY2018Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-991600000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-12900000	USD
CY2018Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-13200000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	300000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-991300000	USD
CY2018Q2	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	21100000	USD
CY2018Q3	ati	Other Comprehensive Income Loss Before Reclassification Adjustments Net Of Tax Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest	-9000000.0	USD
CY2018Q3	ati	Reclassificationfrom Accumulated Other Comprehensive Income Loss Current Period Netof Tax Attributableto Noncontrolling Interest ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest	0	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-9000000.0	USD
CY2018Q3	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	12100000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1027800000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-9300000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-45800000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	36500000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-991300000	USD
CY2017Q4	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	17300000	USD
	ati	Other Comprehensive Income Loss Before Reclassification Adjustments Net Of Tax Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest	-5200000	USD
	ati	Reclassificationfrom Accumulated Other Comprehensive Income Loss Current Period Netof Tax Attributableto Noncontrolling Interest ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest	0	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-5200000	USD
CY2018Q3	ati	Accumulated Other Comprehensive Income Loss Netof Tax Attributableto Noncontrolling Interest AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest	12100000	USD
CY2019Q3	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	19000000	USD
CY2019Q3	us-gaap	Accrued Environmental Loss Contingencies Current AccruedEnvironmentalLossContingenciesCurrent	7000000	USD
CY2019Q3	ati	Environmental Remediation Obligation Federal Superfund Sites EnvironmentalRemediationObligationFederalSuperfundSites	3000000	USD
CY2019Q3	ati	Environmental Remediation Obligation For Formerly Owned Sites EnvironmentalRemediationObligationForFormerlyOwnedSites	14000000	USD
CY2019Q3	ati	Environmental Remediation Obligation For Owned Or Controlled Sites With Closed Operations EnvironmentalRemediationObligationForOwnedOrControlledSitesWithClosedOperations	1000000	USD
CY2019Q3	ati	Environmental Remediation Obligation For Ongoing Operations EnvironmentalRemediationObligationForOngoingOperations	1000000	USD

Files In Submission

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$ATI
ATI INC Stock $ati

2019 Q3 Form 10-Q Financial Statement

#000101896319000024 Filed on November 01, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATI ATI INC Stock $ati

2019 Q3 Form 10-Q Financial Statement

#000101896319000024 Filed on November 01, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ATI
ATI INC Stock $ati