$ATIP
ATI Physical Therapy, Inc. Stock $atip

$atip Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000181584922000006 Filed on March 01, 2022

Income Statement

Concept	2021 Q4	2021 Q3	2021 Q2
Revenue	$155.8M	$159.0M	$164.0M
YoY Change	-73.7%	6.97%	52.23%
Cost Of Revenue	$135.9M	$132.6M	$248.9M
YoY Change	-71.25%
Gross Profit	$19.88M	$26.41M	$64.15M
YoY Change	-83.38%
Gross Profit Margin	12.77%	16.61%	39.11%
Selling, General & Admin	$29.90M	$30.80M	$26.39M
YoY Change	-74.94%	18.32%	6.45%
% of Gross Profit	150.36%	116.6%	41.14%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$10.00M	$9.095M	$9.052M
YoY Change	-74.8%	-7.52%	-6.85%
% of Gross Profit	50.32%	34.44%	14.11%
Operating Expenses	$29.90M	$30.80M	$26.39M
YoY Change	-74.94%	18.32%	6.45%
Operating Profit	-$12.11M	-$516.9M	-$444.3M
YoY Change	-3680.36%	-21034.43%	3154.25%
Interest Expense	-$7.215M	-$7.386M	-$41.81M
YoY Change	-91.83%	-59954.13%
% of Operating Profit
Other Income/Expense, Net	$15.64M	-$52.00K	-$5.626M
YoY Change	-82.82%	-100.22%	-112.76%
Pretax Income	-$3.691M	-$362.1M	-$487.2M
YoY Change	-222.79%	29499.87%	3118914.08%
Income Tax	-$5.381M	-$35.30M	-$19.73M
% Of Pretax Income
Net Earnings	$821.0K	-$324.7M	-$435.4M
YoY Change	-119.87%	-268418.18%	-15983.14%
Net Earnings / Revenue	0.53%	-204.18%	-265.41%
Basic Earnings Per Share	$0.00	-$1.65	-$3.12
Diluted Earnings Per Share	$0.00	-$1.65	-$3.12
COMMON SHARES
Basic Shares Outstanding	197.3M shares	197.0M shares	139.6M shares
Diluted Shares Outstanding	197.4M shares	197.0M shares	139.6M shares

Balance Sheet

Concept	2021 Q4	2021 Q3	2021 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$48.62M	$66.09M	$90.57M
YoY Change	-65.79%	4409.18%	362176.0%
Cash & Equivalents	$48.62M	$66.09M	$90.57M
Short-Term Investments
Other Short-Term Assets	$3.204M	$12.32M	$7.541M
YoY Change	47.79%	2473.23%
Inventory
Prepaid Expenses	$9.303M
Receivables	$82.46M	$85.00M	$87.59M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$143.6M	$163.4M	$185.7M
YoY Change	-39.89%	8304.23%	742688.0%
LONG-TERM ASSETS
Property, Plant & Equipment	$139.7M	$134.9M	$134.0M
YoY Change	1.86%
Goodwill	$608.8M	$603.3M	$910.7M
YoY Change	-54.23%
Intangibles	$411.7M	$411.1M	$611.5M
YoY Change	-36.11%
Long-Term Investments
YoY Change
Other Assets	$2.233M	$1.941M	$1.871M
YoY Change	32.52%		2120.24%
Total Long-Term Assets	$1.419B	$1.405B	$1.915B
YoY Change	-40.16%	307.23%	2272002.3%
TOTAL ASSETS
Total Short-Term Assets	$143.6M	$163.4M	$185.7M
Total Long-Term Assets	$1.419B	$1.405B	$1.915B
Total Assets	$1.563B	$1.568B	$2.100B
YoY Change	-40.14%	352.05%	1922092.83%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$15.15M	$11.02M	$12.26M
YoY Change	24.68%	610.17%	12168.5%
Accrued Expenses	$105.1M	$98.51M	$101.5M
YoY Change	-8.7%	159433.6%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$8.167M	$8.167M	$8.167M
YoY Change	0.0%
Total Short-Term Liabilities	$137.3M	$125.2M	$128.9M
YoY Change	-4.23%	7657.81%	128926.38%
LONG-TERM LIABILITIES
Long-Term Debt	$543.8M	$545.3M	$546.8M
YoY Change	-45.15%
Other Long-Term Liabilities	$2.301M	$7.231M	$7.530M
YoY Change	-87.61%	-40.12%
Total Long-Term Liabilities	$546.1M	$552.5M	$554.3M
YoY Change	-45.93%	4475.69%
TOTAL LIABILITIES
Total Short-Term Liabilities	$137.3M	$125.2M	$128.9M
Total Long-Term Liabilities	$546.1M	$552.5M	$554.3M
Total Liabilities	$1.051B	$1.066B	$1.265B
YoY Change	-38.5%	7689.61%	1265963.67%
SHAREHOLDERS EQUITY
Retained Earnings	-$847.1M	-$855.0M	-$523.3M
YoY Change	1131.22%	68909.58%	3350015.24%
Common Stock	$20.00K	$20.00K	$20.00K
YoY Change	53.85%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$95.00K
YoY Change
Treasury Stock Shares	30.00K shares
Shareholders Equity	$504.4M	$495.2M	$825.5M
YoY Change
Total Liabilities & Shareholders Equity	$1.563B	$1.568B	$2.100B
YoY Change	-40.14%	352.05%	1922092.83%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2021 Q2
OPERATING ACTIVITIES
Net Income	$821.0K	-$324.7M	-$435.4M
YoY Change	-119.87%	-268418.18%	-15983.14%
Depreciation, Depletion And Amortization	$10.00M	$9.095M	$9.052M
YoY Change	-74.8%	-7.52%	-6.85%
Cash From Operating Activities	-$3.437M	-$11.55M	-$25.93M
YoY Change	-102.47%	2463.68%
INVESTING ACTIVITIES
Capital Expenditures	-$12.89M	-$9.865M	-$19.21M
YoY Change	-41.76%
Acquisitions
YoY Change
Other Investing Activities	$1.706M	$105.0K	$240.1K
YoY Change	-99.51%	-100.03%
Cash From Investing Activities	-$11.19M	-$9.760M	-$18.97M
YoY Change	-103.46%	-97.17%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-2.853M	-3.163M	-5.507M
YoY Change	-99.21%	-100.91%	-22128.0%
NET CHANGE
Cash From Operating Activities	-3.437M	-11.55M	-25.93M
Cash From Investing Activities	-11.19M	-9.760M	-18.97M
Cash From Financing Activities	-2.853M	-3.163M	-5.507M
Net Change In Cash	-17.48M	-24.48M	-50.41M
YoY Change	-117.07%	-1798.93%	-201732.32%
FREE CASH FLOW
Cash From Operating Activities	-$3.437M	-$11.55M	-$25.93M
Capital Expenditures	-$12.89M	-$9.865M	-$19.21M
Free Cash Flow	$9.455M	-$1.689M	-$6.719M
YoY Change	-94.13%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0001815849
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	85-1408039
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2021	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2021	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	001-39439
CY2021	dei	Entity Registrant Name EntityRegistrantName	ATI Physical Therapy, Inc.
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	790 Remington Boulevard
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	Bolingbrook
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	IL
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	60440
CY2021	dei	City Area Code CityAreaCode	630
CY2021	dei	Local Phone Number LocalPhoneNumber	296-2223
CY2021	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2021	dei	Entity Small Business EntitySmallBusiness	false
CY2021	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2021	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	false
CY2021	dei	Entity Shell Company EntityShellCompany	false
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CY2021	dei	Auditor Firm AuditorFirmId	238
CY2021	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2021	dei	Auditor Location AuditorLocation	Chicago, Illinois
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CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5073000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	4400000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	-778328000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-5371000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	5349000	USD
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-4.69
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.04
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.04
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-4.69
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.04
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.04
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	165805000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	165805000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2021	us-gaap	Profit Loss ProfitLoss	-782028000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	-298000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	9749000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	1935000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-582000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-16000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-780093000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-880000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	9733000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-3700000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	5073000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	4400000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-776393000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-5953000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	5333000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	898026000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1822000	USD
CY2019	ati	Equity Issued In Acquisition Value EquityIssuedInAcquisitionValue	200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-16000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	4862000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	4400000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	5349000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	904919000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1936000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-582000	USD
CY2020	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	4453000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5073000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-5371000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	901117000	USD
CY2021	ati	Stock Issued During Period Value Reverse Recapitalization StockIssuedDuringPeriodValueReverseRecapitalization	210105000	USD
CY2021	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	300000000	USD
CY2021	us-gaap	Stock Issued During Period Value Conversion Of Convertible Securities StockIssuedDuringPeriodValueConversionOfConvertibleSecurities	128453000	USD
CY2021	ati	Adjustments To Additional Paid In Capital Warrant Liability Recognized In Reverse Recapitalization AdjustmentsToAdditionalPaidInCapitalWarrantLiabilityRecognizedInReverseRecapitalization	26936000	USD
CY2021	ati	Adjustment To Additional Paid In Capital Recognition Of Contingent Shares Liability AdjustmentToAdditionalPaidInCapitalRecognitionOfContingentSharesLiability	220500000	USD
CY2021	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	0	USD
CY2021	ati	Issuance Of Common Stock Upon Vesting Or Exercise Of Equity Awards IssuanceOfCommonStockUponVestingOrExerciseOfEquityAwards	0	USD
CY2021	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	95000	USD
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	5754000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	1935000	USD
CY2021	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	6298000	USD
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-3700000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	-778328000	USD
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	511507000	USD
CY2021	us-gaap	Profit Loss ProfitLoss	-782028000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	-298000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	9749000	USD
CY2021	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	962303000	USD
CY2020	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2019	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	37995000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	39700000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	39104000	USD
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	16369000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	16231000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	22191000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-71088000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	1814000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-44033000	USD
CY2021	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	45536000	USD
CY2020	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	44526000	USD
CY2019	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	0	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	5754000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	1936000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	1822000	USD
CY2021	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	3252000	USD
CY2020	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	4109000	USD
CY2019	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	3197000	USD
CY2021	us-gaap	Paid In Kind Interest PaidInKindInterest	0	USD
CY2020	us-gaap	Paid In Kind Interest PaidInKindInterest	6335000	USD
CY2019	us-gaap	Paid In Kind Interest PaidInKindInterest	0	USD
CY2021	ati	Increase Decrease In Accrued Interest On Redeemable Preferred Stock IncreaseDecreaseInAccruedInterestOnRedeemablePreferredStock	10087000	USD
CY2020	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2021	ati	Gain Loss On Cash Settlement For Outstanding Preferred Stock GainLossOnCashSettlementForOutstandingPreferredStock	-14037000	USD
CY2020	ati	Gain Loss On Cash Settlement For Outstanding Preferred Stock GainLossOnCashSettlementForOutstandingPreferredStock	0	USD
CY2019	ati	Gain Loss On Cash Settlement For Outstanding Preferred Stock GainLossOnCashSettlementForOutstandingPreferredStock	0	USD
CY2020	ati	Increase Decrease In Accrued Interest On Redeemable Preferred Stock IncreaseDecreaseInAccruedInterestOnRedeemablePreferredStock	19031000	USD
CY2019	ati	Increase Decrease In Accrued Interest On Redeemable Preferred Stock IncreaseDecreaseInAccruedInterestOnRedeemablePreferredStock	15511000	USD
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-5534000	USD
CY2021	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	5189000	USD
CY2020	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	-469000	USD
CY2019	us-gaap	Gain Loss On Sales Of Assets And Asset Impairment Charges GainLossOnSalesOfAssetsAndAssetImpairmentCharges	-1870000	USD
CY2021	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	0	USD
CY2020	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	-3863000	USD
CY2019	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	0	USD
CY2021	us-gaap	Fair Value Adjustment Of Warrants FairValueAdjustmentOfWarrants	-22595000	USD
CY2020	us-gaap	Fair Value Adjustment Of Warrants FairValueAdjustmentOfWarrants	0	USD
CY2019	us-gaap	Fair Value Adjustment Of Warrants FairValueAdjustmentOfWarrants	0	USD
CY2021	ati	Change In Fair Value Of Contingent Common Share Liability ChangeInFairValueOfContingentCommonShareLiability	-175140000	USD
CY2020	ati	Change In Fair Value Of Contingent Common Share Liability ChangeInFairValueOfContingentCommonShareLiability	0	USD
CY2019	ati	Change In Fair Value Of Contingent Common Share Liability ChangeInFairValueOfContingentCommonShareLiability	0	USD
CY2021	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	10201000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	3307000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	11929000	USD
CY2021	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	6688000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-4841000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-283000	USD
CY2021	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	284000	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-413000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-36000	USD
CY2021	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	1831000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	798000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	-1908000	USD
CY2021	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-5288000	USD
CY2020	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	9174000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	9543000	USD
CY2021	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-50942000	USD
CY2020	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-42819000	USD
CY2019	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	0	USD
CY2021	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	861000	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	5056000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	2508000	USD
CY2021	ati	Increase Decrease In Medicare Accelerated And Advance Payment Funds IncreaseDecreaseInMedicareAcceleratedAndAdvancePaymentFunds	-12605000	USD
CY2020	ati	Increase Decrease In Medicare Accelerated And Advance Payment Funds IncreaseDecreaseInMedicareAcceleratedAndAdvancePaymentFunds	26732000	USD
CY2019	ati	Increase Decrease In Medicare Accelerated And Advance Payment Funds IncreaseDecreaseInMedicareAcceleratedAndAdvancePaymentFunds	0	USD
CY2021	ati	Transaction Related Amount Due To Former Owners TransactionRelatedAmountDueToFormerOwners	3611000	USD
CY2020	ati	Transaction Related Amount Due To Former Owners TransactionRelatedAmountDueToFormerOwners	0	USD
CY2019	ati	Transaction Related Amount Due To Former Owners TransactionRelatedAmountDueToFormerOwners	0	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-42100000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	138604000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	47944000	USD
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	40293000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	21887000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	41227000	USD
CY2021	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	1675000	USD
CY2020	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	250000	USD
CY2019	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	0	USD
CY2021	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	223000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	328000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	397000	USD
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	4523000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1848000	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-39889000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-21809000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-42678000	USD
CY2021	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	0	USD
CY2020	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	350000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	0	USD
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	456202000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	8167000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	8167000	USD
CY2021	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2020	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	68750000	USD
CY2019	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2021	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2020	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	68750000	USD
CY2019	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	0	USD
CY2021	ati	Proceeds From Reverse Recapitalization ProceedsFromReverseRecapitalization	229338000	USD
CY2020	ati	Proceeds From Reverse Recapitalization ProceedsFromReverseRecapitalization	0	USD
CY2019	ati	Proceeds From Reverse Recapitalization ProceedsFromReverseRecapitalization	0	USD
CY2021	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	59000000	USD
CY2020	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
CY2021	us-gaap	Proceeds From Issuance Of Private Placement ProceedsFromIssuanceOfPrivatePlacement	300000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Private Placement ProceedsFromIssuanceOfPrivatePlacement	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Private Placement ProceedsFromIssuanceOfPrivatePlacement	0	USD
CY2021	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	19233000	USD
CY2020	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	USD
CY2019	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	USD
CY2021	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	128000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2021	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	6298000	USD
CY2020	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	4453000	USD
CY2019	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	4862000	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-11523000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-12970000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-13029000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-93512000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	103825000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-7763000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	142128000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	38303000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	46066000	USD
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	48616000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	142128000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	38303000	USD
CY2021	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-1935000	USD
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	582000	USD
CY2019	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	16000	USD
CY2021	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	4177000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	3010000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	2106000	USD
CY2021	ati	Warrant Liabilities Recognized Upon The Closing Of The Reverse Recapitalization WarrantLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	26936000	USD
CY2020	ati	Warrant Liabilities Recognized Upon The Closing Of The Reverse Recapitalization WarrantLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	0	USD
CY2019	ati	Warrant Liabilities Recognized Upon The Closing Of The Reverse Recapitalization WarrantLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	0	USD
CY2021	ati	Contingent Consideration Common Shares Liabilities Recognized Upon The Closing Of The Reverse Recapitalization ContingentConsiderationCommonSharesLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	220500000	USD
CY2020	ati	Contingent Consideration Common Shares Liabilities Recognized Upon The Closing Of The Reverse Recapitalization ContingentConsiderationCommonSharesLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	0	USD
CY2019	ati	Contingent Consideration Common Shares Liabilities Recognized Upon The Closing Of The Reverse Recapitalization ContingentConsiderationCommonSharesLiabilitiesRecognizedUponTheClosingOfTheReverseRecapitalization	0	USD
CY2021	us-gaap	Stock Issued1 StockIssued1	128453000	USD
CY2020	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2019	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	41937000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	58421000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	76636000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	81000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-1098000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-1092000	USD
CY2021	us-gaap	Nature Of Operations NatureOfOperations	Overview of the Company<div style="margin-bottom:12pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">ATI Physical Therapy, Inc., together with its subsidiaries (herein referred to as “we,” “the Company,” “ATI Physical Therapy” and “ATI”), is a nationally recognized healthcare company, specializing in outpatient rehabilitation and adjacent healthcare services. The Company provides outpatient physical therapy services under the name ATI Physical Therapy and, as of December 31, 2021, had 910 clinics (as well as 20 clinics under management service agreements) located in 25 states. The Company offers a variety of services within its clinics, including physical therapy to treat spine, shoulder, knee and neck injuries or pain; work injury rehabilitation services, including work conditioning and work hardening; hand therapy; and other specialized treatment services. The Company’s direct and indirect wholly-owned subsidiaries include, but are not limited to, Wilco Holdco, Inc., ATI Holdings Acquisition, Inc. and ATI Holdings, LLC.</span></div><div style="margin-bottom:12pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On June 16, 2021 (the “Closing Date”), a Business Combination transaction (the “Business Combination”) was finalized pursuant to the Agreement and Plan of Merger ("Merger Agreement"), dated February 21, 2021 between the operating company, Wilco Holdco, Inc. (“Wilco Holdco”), and Fortress Value Acquisition Corp. II (herein referred to as "FAII" and "FVAC"), a special purpose acquisition company. In connection with the closing of the Business Combination, the Company changed its name from Fortress Value Acquisition Corp. II to ATI Physical Therapy, Inc. The Company’s common stock is listed on the New York Stock Exchange ("NYSE") under the symbol “ATIP.”</span></div><div style="margin-bottom:12pt;text-align:justify"><span style="background-color:#ffffff;color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Business Combination is accounted for as a reverse recapitalization in accordance with U.S. generally accepted accounting principles ("GAAP"). Under </span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">this method of accounting, FAII is treated as the acquired company and Wilco Holdco is treated as the acquirer for financial statement reporting and accounting purposes. As a result, the historical operations of Wilco Holdco are deemed to be those of the Company. Therefore, the financial statements included in this report reflect (i) the historical operating results of Wilco Holdco prior to the Business Combination; (ii) the combined results of FAII and Wilco Holdco following the Business Combination on June 16, 2021; (iii) the assets and liabilities of Wilco Holdco at their historical cost; and (iv) the Company’s equity structure for all periods presented. The recapitalization of the number of shares of common stock attributable to the Business Combination is reflected retroactively to the earliest period presented and will be utilized for calculating earnings per share in all prior periods presented. No step-up basis of intangible assets or goodwill was recorded in the Business Combination consistent with the treatment of the transaction as a reverse recapitalization of Wilco Holdco, Inc. Refer to Note 3 - </span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Business Combinations and Divestiture</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> for additional information.</span></div><div style="margin-bottom:6pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Impact of COVID-19 and CARES Act</span></div><div style="margin-bottom:12pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The coronavirus ("COVID-19") pandemic in the United States resulted in changes to our operating environment. We continue to closely monitor the impact of COVID-19 on all aspects of our business, and our priorities remain protecting the health and safety of employees and patients, maximizing the availability of services to satisfy patient needs and improving the operational and financial stability of our business. While we expect the disruption caused by COVID-19 and resulting impacts to diminish over time, we cannot predict the length of such impacts, and if such impacts continue for an extended period, it could have a continued effect on the Company’s results of operations, financial condition and cash flows, which could be material.</span></div><div style="margin-bottom:12pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) was signed into law providing reimbursement, grants, waivers and other funds to assist health care providers during the COVID-19 pandemic. The Company has realized benefits under the CARES Act including, but not limited to, the following: </span></div><div style="padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">In 2020, the Company received approximately $91.5 million of general distribution payments under the Provider Relief Fund. These payments have been recognized as other income in the consolidated statements of operations throughout 2020 in a manner commensurate with the reporting and eligibility requirements issued by HHS. Based on the terms and conditions of the program, including reporting guidance issued by HHS in 2021, the Company believes that it has met the applicable terms and conditions. This includes, but is not limited to, the fact that the Company’s COVID-19 related expenses and lost revenues for the year ended December 31, 2020 exceeded the amount of funds received. To the extent that reporting requirements and terms and conditions are subsequently modified, it may affect the Company’s ability to comply and ability to retain the funds. The following table summarizes the quarterly recognition of general distribution payments recognized in other expense (income), net in the Company's 2020 consolidated statements of operations (in millions):</span></div><div style="text-align:justify;text-indent:36pt"><span><br/></span></div><div style="margin-bottom:0.08pt;text-align:justify"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.519%"><tr><td style="width:1.0%"/><td style="width:18.384%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.444%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.384%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.444%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.384%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.444%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.384%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.444%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.388%"/><td style="width:0.1%"/></tr><tr><td colspan="21" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Three Months Ended</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/></tr><tr><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">March 31, 2020</span></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">June 30, 2020</span></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">September 30, 2020</span></td><td colspan="3" style="border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">December 31, 2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Total</span></td></tr><tr><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">— </span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccecff;padding:0 1pt"/><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(44.3)</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccecff;padding:0 1pt"/><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(23.1)</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccecff;padding:0 1pt"/><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(24.1)</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ccecff;padding:0 1pt"/><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(91.5)</span></td><td style="background-color:#ccecff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="text-align:justify"><span><br/></span></div><div style="margin-bottom:12pt;padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The Company applied for and obtained approval to receive $26.7 million of Medicare Accelerated and Advance Payment Program ("MAAPP") funds during the quarter ended June 30, 2020. During the year ended December 31, 2021, the Company applied $12.6 million in MAAPP funds and transferred $1.8 million in MAAPP funds as part of the divestiture of its Home Health service line. Because the Company has not yet met all required performance obligations or performed the services related to the remaining funds, as of December 31, 2021 and December 31, 2020, $12.3 million and $15.5 million of the funds are recorded in accrued expenses and other liabilities, respectively, and zero and $11.2 million of the funds are recorded in other non-current liabilities, respectively.</span></div><div style="margin-bottom:14pt;padding-left:36pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The Company elected to defer depositing the employer portion of Social Security taxes for payments due from March 27, 2020 through December 31, 2020, interest-free and penalty-free. Related to these payments, as of December 31, 2021 and December 31, 2020, $5.9 million and $5.5 million is included in accrued expenses and other liabilities, respectively, and zero and $5.5 million is included in other non-current liabilities, respectively.</span></div>
CY2021Q4	us-gaap	Number Of Stores NumberOfStores	910	clinic
CY2021Q4	ati	Number Of Stores Under Management Service Agreements NumberOfStoresUnderManagementServiceAgreements	20	clinic
CY2021Q4	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	25	state
CY2021	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:6pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:700;line-height:120%">U</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">se of estimates</span></div><div style="margin-bottom:12pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. The effect of the change in the estimates will be recognized in the current period of the change.</span></div>
CY2021	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2021	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	Concentrations of business riskThe Company provides physical therapy services to a large number of patients who participate in government healthcare programs, resulting in a customer concentration relating to Medicare and Medicaid’s service reimbursement programs. The Company believes that the concentration of credit risk with respect to other patient accounts receivable is limited due to the large number of patients that make up the Company’s patient base and the dispersion across many different insurance companies, preferred provider organizations and individuals.
CY2021	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2300000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	3000000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2700000	USD
CY2020	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	1000000	USD
CY2021	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	1000000	USD
CY2019	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	500000	USD
CY2021Q2	ati	Recapitalization Exchange Ratio RecapitalizationExchangeRatio	136.7
CY2021Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	207300000	shares
CY2021Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	196600000	shares
CY2021Q2	us-gaap	Stock Issued During Period Shares Acquisitions StockIssuedDuringPeriodSharesAcquisitions	34137000	shares
CY2021Q2	ati	Stock Converted Reverse Recapitalization Shares StockConvertedReverseRecapitalizationShares	130300000	shares
CY2021Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	30000000	shares
CY2021Q2	us-gaap	Stock Issued During Period Shares Conversion Of Convertible Securities StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities	12845000	shares
CY2021Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	207282000	shares
CY2021Q2	ati	Common Stock Shares Issued Vesting Shares CommonStockSharesIssuedVestingShares	8625000	shares
CY2021Q2	ati	Common Stock Shares Issued Restricted CommonStockSharesIssuedRestricted	2014000	shares
CY2021Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	196643000	shares
CY2021Q2	ati	Fair Value Disclosure Warrant Liability FairValueDisclosureWarrantLiability	26900000	USD
CY2021Q4	ati	Fair Value Disclosure Warrant Liability FairValueDisclosureWarrantLiability	4300000	USD
CY2021	us-gaap	Fair Value Adjustment Of Warrants FairValueAdjustmentOfWarrants	-22600000	USD
CY2021Q2	ati	Cash Acquired Through Reverse Recapitalization CashAcquiredThroughReverseRecapitalization	345036000	USD
CY2021Q2	us-gaap	Payments For Repurchase Of Equity PaymentsForRepurchaseOfEquity	89877000	USD
CY2021Q2	ati	Payments Of Reverse Recapitalization Transaction Costs PaymentsOfReverseRecapitalizationTransactionCosts	25821000	USD
CY2021Q2	ati	Proceeds From Reverse Recapitalization ProceedsFromReverseRecapitalization	229338000	USD
CY2021Q2	ati	Reverse Recapitalization Transaction Cost Offset Against Proceeds ReverseRecapitalizationTransactionCostOffsetAgainstProceeds	19233000	USD
CY2021Q2	ati	Proceeds From Reverse Recapitalization Transaction Net Of Transaction Cost ProceedsFromReverseRecapitalizationTransactionNetOfTransactionCost	210105000	USD
CY2021Q2	us-gaap	Proceeds From Issuance Of Private Placement ProceedsFromIssuanceOfPrivatePlacement	300000000	USD
CY2016Q2	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	59000000	USD
CY2021	ati	Reverse Recapitalization Transaction Cost ReverseRecapitalizationTransactionCost	5543000	USD
CY2021	ati	Net Increase Decrease In Cash Related To Reverse Recapitalization NetIncreaseDecreaseInCashRelatedToReverseRecapitalization	-2473000	USD
CY2021	ati	Reverse Recapitalization Transaction Cost ReverseRecapitalizationTransactionCost	5500000	USD
CY2021Q2	ati	Adjustments To Additional Paid In Capital Recapitalization Transaction Costs AdjustmentsToAdditionalPaidInCapitalRecapitalizationTransactionCosts	19200000	USD
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	627871000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	592253000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	785458000	USD
CY2021	us-gaap	Number Of Reporting Units NumberOfReportingUnits	1	unit
CY2020Q4	us-gaap	Goodwill Goodwill	1330085000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1330085000	USD
CY2021	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	726798000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2021	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	5524000	USD
CY2020	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	0	USD
CY2021Q4	us-gaap	Goodwill Goodwill	608811000	USD
CY2020	us-gaap	Depreciation Depreciation	39510000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1330085000	USD
CY2021Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	411696000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	644339000	USD
CY2021Q2	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	419400000	USD
CY2021Q3	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	307400000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	336135000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	300081000	USD
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	196405000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	162907000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	139730000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	137174000	USD
CY2021	us-gaap	Depreciation Depreciation	37537000	USD
CY2019	us-gaap	Depreciation Depreciation	40119000	USD
CY2021Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	27257000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	21387000	USD
CY2021Q4	ati	Medicare Accelerated And Advance Payment Funds And Deferred Employer Social Security Tax Cares Act Current MedicareAcceleratedAndAdvancePaymentFundsAndDeferredEmployerSocialSecurityTaxCARESActCurrent	18179000	USD
CY2020Q4	ati	Medicare Accelerated And Advance Payment Funds And Deferred Employer Social Security Tax Cares Act Current MedicareAcceleratedAndAdvancePaymentFundsAndDeferredEmployerSocialSecurityTaxCARESActCurrent	21031000	USD
CY2021Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	4574000	USD
CY2020Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	2049000	USD
CY2021Q4	us-gaap	Health Care Organization Accounts Payable To Third Party Payor HealthCareOrganizationAccountsPayableToThirdPartyPayor	4240000	USD
CY2020Q4	us-gaap	Health Care Organization Accounts Payable To Third Party Payor HealthCareOrganizationAccountsPayableToThirdPartyPayor	9635000	USD
CY2021Q4	ati	Revenue Cycle Management Costs Current RevenueCycleManagementCostsCurrent	1075000	USD
CY2020Q4	ati	Revenue Cycle Management Costs Current RevenueCycleManagementCostsCurrent	2469000	USD
CY2021Q4	ati	Accrued Transaction Related Cost Current AccruedTransactionRelatedCostCurrent	349000	USD
CY2020Q4	ati	Accrued Transaction Related Cost Current AccruedTransactionRelatedCostCurrent	2547000	USD
CY2021Q4	ati	Transaction Related Amount Due To Former Owners Current TransactionRelatedAmountDueToFormerOwnersCurrent	0	USD
CY2020Q4	ati	Transaction Related Amount Due To Former Owners Current TransactionRelatedAmountDueToFormerOwnersCurrent	3611000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	5500000	USD
CY2021Q4	us-gaap	Accounts Payable And Other Accrued Liabilities Current AccountsPayableAndOtherAccruedLiabilitiesCurrent	8910000	USD
CY2020Q4	us-gaap	Accounts Payable And Other Accrued Liabilities Current AccountsPayableAndOtherAccruedLiabilitiesCurrent	7961000	USD
CY2021Q4	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	64584000	USD
CY2020Q4	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	70690000	USD
CY2021Q4	us-gaap	Debt Instrument Unamortized Discount DebtInstrumentUnamortizedDiscount	1935000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount DebtInstrumentUnamortizedDiscount	8933000	USD
CY2021Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	1147000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	2732000	USD
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	551966000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	999585000	USD
CY2021Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	8167000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	8167000	USD
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	543799000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	991418000	USD
CY2021	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-5500000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	8167000	USD
CY2021Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	546881000	USD
CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	555048000	USD
CY2021Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	3082000	USD
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	551966000	USD
CY2021	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	1
CY2021	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	0.50
CY2021	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.06
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4600000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4700000	USD
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4634000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	4726000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	5469000	USD
CY2021Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	1000000	shares
CY2021Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.0001
CY2021Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2021Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2021Q2	ati	Recapitalization Exchange Ratio RecapitalizationExchangeRatio	136.7
CY2021Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	53811000	shares
CY2021	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	30000.00	shares
CY2021Q2	ati	Gain Loss On Cash Settlement For Outstanding Preferred Stock GainLossOnCashSettlementForOutstandingPreferredStock	-14000000	USD
CY2021Q4	us-gaap	Shares Subject To Mandatory Redemption Settlement Terms Amount Noncurrent SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent	0	USD
CY2020Q4	us-gaap	Shares Subject To Mandatory Redemption Settlement Terms Amount Noncurrent SharesSubjectToMandatoryRedemptionSettlementTermsAmountNoncurrent	163300000	USD
CY2021Q2	ati	Warrant Liability Noncurrent WarrantLiabilityNoncurrent	26936000	USD
	us-gaap	Fair Value Adjustment Of Warrants FairValueAdjustmentOfWarrants	22595000	USD
CY2021Q4	ati	Warrant Liability Noncurrent WarrantLiabilityNoncurrent	4341000	USD
CY2021Q4	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	11.50
CY2021	ati	Class Of Warrant Or Right Exercise Period ClassOfWarrantOrRightExercisePeriod	P30D
CY2021	ati	Class Of Warrant Or Right Expiration Period ClassOfWarrantOrRightExpirationPeriod	P5Y
CY2021Q2	ati	Class Of Warrant Or Right Period Warrants Are Not Transferable Assignable Or Salable After Business Combination ClassOfWarrantOrRightPeriodWarrantsAreNotTransferableAssignableOrSalableAfterBusinessCombination	P30D
CY2021Q2	ati	Number Of Tranches NumberOfTranches	3	tranche
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	14000	USD
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	128000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	251000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	14000	USD
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	128000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	251000	USD
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-60002000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	3514000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-30305000	USD
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-11086000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1700000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-13728000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-71088000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	1814000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-44033000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-70960000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2065000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44019000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.083
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.625
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	1.138
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-179128000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-694000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-8121000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-25814000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.030
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1248000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.378
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-3741000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.097
CY2021	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	34000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2020	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-2551000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0.771
CY2019	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-1197000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0.031
CY2021	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	1515000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.002
CY2020	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-105000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	0.032
CY2019	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-51000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	0
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	35731000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.042
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-981000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.297
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-34943000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.904
CY2021	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStock	2118000	USD
CY2021	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock Percent EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStockPercent	-0.002
CY2020	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStock	3997000	USD
CY2020	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock Percent EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStockPercent	-1.209
CY2019	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStock	3257000	USD
CY2019	ati	Effective Income Tax Rate Reconciliation Interest Expense On Redeemable Preferred Stock Percent EffectiveIncomeTaxRateReconciliationInterestExpenseOnRedeemablePreferredStockPercent	-0.084
CY2021	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiability	-41524000	USD
CY2021	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability Percent EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiabilityPercent	0.049
CY2020	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiability	0	USD
CY2020	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability Percent EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiabilityPercent	0
CY2019	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiability	0	USD
CY2019	ati	Effective Income Tax Reconciliation Change In Fair Value Of Warrant Liability And Contingent Common Shares Liability Percent EffectiveIncomeTaxReconciliationChangeInFairValueOfWarrantLiabilityAndContingentCommonSharesLiabilityPercent	0
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	132447000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	-0.155
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	3661000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	-0.005
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	1151000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	-0.348
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	777000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	-0.020
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-70960000	USD
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.083
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2065000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.625
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44019000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	1.138
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	10420000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	14423000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	12530000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	16472000	USD
CY2021Q4	ati	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	74115000	USD
CY2020Q4	ati	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	75141000	USD
CY2021Q4	ati	Deferred Tax Assets Acquisition And Transaction Costs DeferredTaxAssetsAcquisitionAndTransactionCosts	3770000	USD
CY2020Q4	ati	Deferred Tax Assets Acquisition And Transaction Costs DeferredTaxAssetsAcquisitionAndTransactionCosts	4262000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	82304000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	54655000	USD
CY2021Q4	ati	Deferred Tax Assets Interest Expense DeferredTaxAssetsInterestExpense	33163000	USD
CY2020Q4	ati	Deferred Tax Assets Interest Expense DeferredTaxAssetsInterestExpense	21903000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	4798000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	4205000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	221100000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	191061000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	58312000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	22581000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	162788000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	168480000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Goodwill DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsGoodwill	26563000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Goodwill DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsGoodwill	36374000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	114451000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	179503000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	63252000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	63531000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	22089000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	24188000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3892000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3431000	USD
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	230247000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	307027000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	67459000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	138547000	USD
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3027000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2341000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	884000	USD
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	686000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1457000	USD
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3027000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2020	ati	Lease Modification Operation Lease Liabilities Additions LeaseModificationOperationLeaseLiabilitiesAdditions	29300000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	64314000	USD
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3027000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2341000	USD
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	65555000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	67279000	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	20045000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	18689000	USD
CY2021	us-gaap	Lease Cost LeaseCost	85600000	USD
CY2020	us-gaap	Lease Cost LeaseCost	85968000	USD
CY2020	ati	Lessee Lease Termination Costs LesseeLeaseTerminationCosts	4300000	USD
CY2020	us-gaap	Gain Loss On Termination Of Lease GainLossOnTerminationOfLease	-3900000	USD
CY2020	ati	Lessee Lease Termination Costs Other LesseeLeaseTerminationCostsOther	400000	USD
CY2021	ati	Payments For Lease Terminations PaymentsForLeaseTerminations	4600000	USD
CY2021	ati	Lease Modification Operation Lease Liabilities Additions LeaseModificationOperationLeaseLiabilitiesAdditions	18400000	USD
CY2021	ati	Lease Modification Operating Lease Assets Additions LeaseModificationOperatingLeaseAssetsAdditions	18400000	USD
CY2020	ati	Lease Modification Operating Lease Assets Additions LeaseModificationOperatingLeaseAssetsAdditions	29300000	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	65678000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	61993000	USD
CY2021	ati	Payments For Lease Terminations PaymentsForLeaseTerminations	4570000	USD
CY2020	ati	Payments For Lease Terminations PaymentsForLeaseTerminations	0	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	28759000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	14067000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y4M24D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y8M12D
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	6.5
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	6.5
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	66916000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	57370000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	48508000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	42278000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	92133000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	371519000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	71489000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	300030000	USD
CY2021Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	49433000	USD
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	250597000	USD
CY2021Q4	us-gaap	Contractual Obligation ContractualObligation	4800000	USD
CY2021	us-gaap	Profit Loss ProfitLoss	-782028000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	-298000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	9749000	USD
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-3700000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5073000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	4400000	USD
CY2021	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	0	USD
CY2020	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	0	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	535000	USD
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-778328000	USD
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-778328000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-5371000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-5371000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	4814000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	4814000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	165805000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	165805000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-4.69
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-4.69
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.04
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.04
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.04
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.04
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	12817000	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2021Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	149062000	USD
CY2021Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	164033000	USD
CY2021Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	159013000	USD
CY2021Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	155763000	USD
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-4.69
CY2021Q4	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	137978000	USD
CY2021	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	533797000	USD
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	627871000	USD
CY2021Q1	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	131121000	USD
CY2021Q2	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	128581000	USD
CY2021Q3	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	136117000	USD
CY2021Q1	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	24726000	USD
CY2021Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	26391000	USD
CY2021Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	30795000	USD
CY2021Q4	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	29897000	USD
CY2021	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	111809000	USD
CY2021Q1	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2021Q2	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	453331000	USD
CY2021Q3	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	508972000	USD
CY2021Q4	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2021	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	962303000	USD
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.65
CY2021Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.00
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-4.69
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.15
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-3.12
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.65
CY2021Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	-6785000	USD
CY2021Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	-444270000	USD
CY2021Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	-516871000	USD
CY2021Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	-12112000	USD
CY2021	us-gaap	Operating Income Loss OperatingIncomeLoss	-980038000	USD
CY2021Q1	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-28333000	USD
CY2021Q2	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-458857000	USD
CY2021Q3	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-362107000	USD
CY2021Q4	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-3691000	USD
CY2021	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-852988000	USD
CY2021Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-10515000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19731000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-35333000	USD
CY2021Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5381000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-70960000	USD
CY2021Q1	us-gaap	Profit Loss ProfitLoss	-17818000	USD
CY2021Q2	us-gaap	Profit Loss ProfitLoss	-439126000	USD
CY2021Q3	us-gaap	Profit Loss ProfitLoss	-326774000	USD
CY2021Q4	us-gaap	Profit Loss ProfitLoss	1690000	USD
CY2021	us-gaap	Profit Loss ProfitLoss	-782028000	USD
CY2021Q1	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	1309000	USD
CY2021Q2	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-3769000	USD
CY2021Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-2109000	USD
CY2021Q4	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	869000	USD
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-3700000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	-19127000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	-435357000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	-324665000	USD
CY2021Q4	us-gaap	Net Income Loss NetIncomeLoss	821000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	-778328000	USD
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.15
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-3.12
CY2021Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.00
CY2021Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	139553000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139553000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	196996000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	196996000	shares
CY2021Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	197285000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	165805000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	165805000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	128286000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	128286000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	139553000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139553000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	196996000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	196996000	shares
CY2021Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	197446000	shares
	us-gaap	Net Income Loss NetIncomeLoss	-454484000	USD
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-3.39
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	165805000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	165805000	shares
CY2021Q2	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	453331000	USD
CY2021Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	-444270000	USD
CY2021Q2	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-458857000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19731000	USD
CY2021Q2	us-gaap	Profit Loss ProfitLoss	-439126000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	-435357000	USD
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-3.12
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-3.12
	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	453331000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	-451055000	USD
	us-gaap	Income Loss Including Portion Attributable To Noncontrolling Interest IncomeLossIncludingPortionAttributableToNoncontrollingInterest	-487190000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-30246000	USD
	us-gaap	Profit Loss ProfitLoss	-456944000	USD
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-3.39
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-35300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-65600000	USD
CY2021Q3	us-gaap	Profit Loss ProfitLoss	-326800000	USD
	us-gaap	Profit Loss ProfitLoss	-783700000	USD
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.65
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-5.02

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$ATIP
ATI Physical Therapy, Inc. Stock $atip

2021 Q4 Form 10-K Financial Statement

#000181584922000006 Filed on March 01, 2022

Income Statement

Balance Sheet

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$ATIP ATI Physical Therapy, Inc. Stock $atip

2021 Q4 Form 10-K Financial Statement

#000181584922000006 Filed on March 01, 2022

Income Statement

Balance Sheet

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Facts In Submission

Files In Submission

$ATIP
ATI Physical Therapy, Inc. Stock $atip