$ASGN
ASGN Inc Stock $asgn

$asgn Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000089056422000007 Filed on March 01, 2022

Income Statement

Concept	2021 Q4	2021 Q3	2021
Revenue	$1.054B	$1.074B	$4.010B
YoY Change	17.04%	18.73%	14.49%
Cost Of Revenue	$740.1M	$765.1M	$2.867B
YoY Change	0.72%	14.52%	12.22%
Gross Profit	$313.7M	$308.7M	$1.142B
YoY Change	30.27%	30.64%	20.61%
Gross Profit Margin	29.77%	28.75%	28.49%
Selling, General & Admin	$202.4M	$192.7M	$735.8M
YoY Change	12.51%	28.38%	19.64%
% of Gross Profit	64.52%	62.42%	64.41%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$22.10M	$7.100M	$89.60M
YoY Change	-8.3%	-5.33%	-0.11%
% of Gross Profit	7.04%	2.3%	7.84%
Operating Expenses	$218.2M	$192.7M	$735.8M
YoY Change	12.47%	28.38%	19.64%
Operating Profit	$95.50M	$100.1M	$350.9M
YoY Change	104.06%	36.19%	24.79%
Interest Expense	-$9.300M	$9.600M	$37.50M
YoY Change	0.0%	3.23%	-5.54%
% of Operating Profit	-9.74%	9.59%	10.69%
Other Income/Expense, Net
YoY Change
Pretax Income	$86.20M	$90.50M	$313.4M
YoY Change	17.6%	40.97%	29.77%
Income Tax	$20.80M	$24.20M	$81.60M
% Of Pretax Income	24.13%	26.74%	26.04%
Net Earnings	$85.00M	$212.0M	$409.9M
YoY Change	53.43%	305.35%	104.64%
Net Earnings / Revenue	8.07%	19.74%	10.22%
Basic Earnings Per Share	$1.64	$4.02	$7.78
Diluted Earnings Per Share	$1.62	$3.97	$7.66
COMMON SHARES
Basic Shares Outstanding	52.00M shares	52.70M shares	52.70M shares
Diluted Shares Outstanding	52.90M shares	53.40M shares	53.50M shares

Balance Sheet

Concept	2021 Q4	2021 Q3	2021
SHORT-TERM ASSETS
Cash & Short-Term Investments	$529.6M	$679.4M	$529.6M
YoY Change	93.0%	195.78%	93.0%
Cash & Equivalents	$529.6M	$679.4M	$529.6M
Short-Term Investments
Other Short-Term Assets	$30.40M	$34.20M	$71.60M
YoY Change	75.72%	87.91%	73.37%
Inventory
Prepaid Expenses	$41.20M	$10.90M
Receivables	$708.2M	$697.7M	$708.2M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.309B	$1.422B	$1.309B
YoY Change	31.68%	52.16%	31.68%
LONG-TERM ASSETS
Property, Plant & Equipment	$55.00M	$52.10M	$112.1M
YoY Change	0.18%	-29.78%	-27.35%
Goodwill	$1.570B	$1.563B
YoY Change	10.47%	-1.78%
Intangibles	$730.5M	$752.5M
YoY Change	2.53%	-0.42%
Long-Term Investments
YoY Change
Other Assets	$23.90M	$22.50M	$23.90M
YoY Change	16.02%	3.21%	3.91%
Total Long-Term Assets	$2.193B	$2.204B	$2.193B
YoY Change	-3.95%	-3.19%	-3.95%
TOTAL ASSETS
Total Short-Term Assets	$1.309B	$1.422B	$1.309B
Total Long-Term Assets	$2.193B	$2.204B	$2.193B
Total Assets	$3.503B	$3.627B	$3.503B
YoY Change	6.86%	12.92%	6.86%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$20.10M	$32.00M	$20.10M
YoY Change	-47.52%	-36.13%	-49.5%
Accrued Expenses	$328.8M	$335.5M	$328.8M
YoY Change	11.27%	25.42%	11.27%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$450.9M	$591.0M	$450.9M
YoY Change	8.34%	51.77%	8.34%
LONG-TERM LIABILITIES
Long-Term Debt	$1.034B	$1.034B	$1.034B
YoY Change	0.05%	0.03%	0.05%
Other Long-Term Liabilities	$23.40M	$62.00M	$63.60M
YoY Change	-64.49%	-29.06%	-52.04%
Total Long-Term Liabilities	$1.057B	$62.00M	$1.098B
YoY Change	-3.82%	-29.06%	-5.87%
TOTAL LIABILITIES
Total Short-Term Liabilities	$450.9M	$591.0M	$450.9M
Total Long-Term Liabilities	$1.057B	$62.00M	$1.098B
Total Liabilities	$1.637B	$1.792B	$1.637B
YoY Change	-3.16%	6.2%	-3.16%
SHAREHOLDERS EQUITY
Retained Earnings	$1.174B	$1.146B
YoY Change	26.78%	31.53%
Common Stock	$691.3M	$689.2M
YoY Change	4.46%	4.71%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.865B	$1.834B	$1.865B
YoY Change
Total Liabilities & Shareholders Equity	$3.503B	$3.627B	$3.503B
YoY Change	6.86%	12.92%	6.86%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2021
OPERATING ACTIVITIES
Net Income	$85.00M	$212.0M	$409.9M
YoY Change	53.43%	305.35%	104.64%
Depreciation, Depletion And Amortization	$22.10M	$7.100M	$89.60M
YoY Change	-8.3%	-5.33%	-0.11%
Cash From Operating Activities	-$82.20M	$71.20M	$193.7M
YoY Change	-194.48%	-18.72%	-54.4%
INVESTING ACTIVITIES
Capital Expenditures	-$9.100M	-$8.000M	$34.70M
YoY Change	111.63%	40.35%	6.44%
Acquisitions			$222.8M
YoY Change			19.66%
Other Investing Activities	$6.400M	$360.6M	-$200.0K
YoY Change	-118.5%	-646.36%	-200.0%
Cash From Investing Activities	-$2.700M	$352.6M	$246.5M
YoY Change	-93.06%	-591.77%	-212.56%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$181.3M
YoY Change			549.82%
Debt Paid & Issued, Net			$0.00
YoY Change			-100.0%
Cash From Financing Activities	-65.00M	-119.5M	-$184.4M
YoY Change	1313.04%	-2589.58%	535.86%
NET CHANGE
Cash From Operating Activities	-82.20M	71.20M	$193.7M
Cash From Investing Activities	-2.700M	352.6M	$246.5M
Cash From Financing Activities	-65.00M	-119.5M	-$184.4M
Net Change In Cash	-149.9M	304.3M	$255.2M
YoY Change	-444.6%	1370.05%	42.41%
FREE CASH FLOW
Cash From Operating Activities	-$82.20M	$71.20M	$193.7M
Capital Expenditures	-$9.100M	-$8.000M	$34.70M
Free Cash Flow	-$73.10M	$79.20M	$159.0M
YoY Change	-180.07%	-15.11%	-59.46%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Entity Central Index Key EntityCentralIndexKey	0000890564
CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021	dei	Amendment Flag AmendmentFlag	false
CY2021	dei	Document Type DocumentType	10-K
CY2021	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	23060
CY2021	dei	Document Annual Report DocumentAnnualReport	true
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	001-35636
CY2021	dei	Entity Registrant Name EntityRegistrantName	ASGN Inc
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	95-4023433
CY2021	dei	Entity Address Address Line1 EntityAddressAddressLine1	4400 Cox Road, Suite 110
CY2021	dei	Entity Address City Or Town EntityAddressCityOrTown	Glen Allen,
CY2021	dei	Entity Address State Or Province EntityAddressStateOrProvince	VA
CY2021	dei	City Area Code CityAreaCode	888
CY2021	dei	Local Phone Number LocalPhoneNumber	482-8068
CY2021	dei	Security12b Title Security12bTitle	Common Stock
CY2021	dei	Trading Symbol TradingSymbol	ASGN
CY2021	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2021	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2021	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2021	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
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	true
CY2021	dei	Entity Shell Company EntityShellCompany	false
CY2021Q2	dei	Entity Public Float EntityPublicFloat	5000000000	USD
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CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Auditor Name AuditorName	DELOITTE & TOUCHE LLP
CY2021	dei	Auditor Location AuditorLocation	Los Angeles, California
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CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.43
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.48
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.66
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.76
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.28
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52800000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53500000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53300000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53400000	shares
CY2021	us-gaap	Net Income Loss NetIncomeLoss	409900000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	200300000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	174700000	USD
CY2021	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	700000	USD
CY2020	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	6000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-700000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	410600000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	206300000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	174000000.0	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1182100000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	39500000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	12700000	USD
CY2019	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	12100000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	20000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-700000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	174700000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1376200000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	32400000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	12100000	USD
CY2020	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	12000000.0	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	27900000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	6000000.0	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	200300000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1587100000	USD
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	52700000	USD
CY2021	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	14300000	USD
CY2021	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	16000000.0	USD
CY2021	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	183300000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	700000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	409900000	USD
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1865400000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	409900000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	200300000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	174700000	USD
CY2021	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	216900000	USD
CY2020	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	0	USD
CY2019	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	0	USD
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	89600000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	89700000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	91200000	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	52700000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	32300000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	39300000	USD
CY2021	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-19700000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	1300000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	18900000	USD
CY2021	us-gaap	Write Off Of Deferred Debt Issuance Cost WriteOffOfDeferredDebtIssuanceCost	0	USD
CY2020	us-gaap	Write Off Of Deferred Debt Issuance Cost WriteOffOfDeferredDebtIssuanceCost	0	USD
CY2019	us-gaap	Write Off Of Deferred Debt Issuance Cost WriteOffOfDeferredDebtIssuanceCost	18900000	USD
CY2021	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-6300000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-5900000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-16000000.0	USD
CY2021	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	111100000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	12900000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	24300000	USD
CY2021	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	18200000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-6500000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	20800000	USD
CY2021	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-23600000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	800000	USD
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	222800000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-7300000	USD
CY2021	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	67400000	USD
CY2020	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	12600000	USD
CY2019	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	5000000.0	USD
CY2021	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	1700000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-300000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-2200000	USD
CY2021	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	44400000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-88600000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-3800000	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	193700000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	424800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	313200000	USD
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	34700000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	32600000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	32700000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	186200000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	116400000	USD
CY2020	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-200000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	200000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	246500000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-219000000.0	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-149100000	USD
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	65500000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	653000000.0	USD
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	65500000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	736200000	USD
CY2021	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	1400000	USD
CY2020	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	1200000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	7800000	USD
CY2021	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	14300000	USD
CY2020	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	12100000	USD
CY2019	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	12700000	USD
CY2021	asgn	Payments For Issuance Of Equity Instruments Employment Taxes PaymentsForIssuanceOfEquityInstrumentsEmploymentTaxes	16000000.0	USD
CY2020	asgn	Payments For Issuance Of Equity Instruments Employment Taxes PaymentsForIssuanceOfEquityInstrumentsEmploymentTaxes	12000000.0	USD
CY2019	asgn	Payments For Issuance Of Equity Instruments Employment Taxes PaymentsForIssuanceOfEquityInstrumentsEmploymentTaxes	12200000	USD
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	181300000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	27900000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	20000000.0	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-184400000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-29000000.0	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-110500000	USD
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-600000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2400000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-200000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	255200000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	179200000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	53400000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	274400000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	95200000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	41800000	USD
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	529600000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	274400000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	95200000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	170300000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	64200000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	56600000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	35200000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	37600000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	44900000	USD
CY2021	us-gaap	Basis Of Accounting BasisOfAccounting	<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Basis of Presentation</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> — The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") and the rules of the Securities and Exchange Commission ("SEC"). The consolidated financial statements include the accounts of ASGN Incorporated and its wholly-owned subsidiaries ("ASGN" or the "Company"). The results of operations for acquired companies are included in the consolidated results of the Company from the date of acquisition (see </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Note 6. Acquisitions</span><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:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> All intercompany accounts and transactions have been eliminated. Certain prior period amounts have been reclassified to conform to current period presentation. In addition, retrospective reclassifications have been made to prior period consolidated financial statements and disclosures to present the Oxford Global Resources business unit (the "Oxford business") as discontinued operations (see </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Note 4. Discontinued Operations</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">). Unless otherwise noted, amounts and disclosures included herein relate to our continuing operations. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Use of Estimates —</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> The preparation of financial statements in conformity 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 financial statements and the reported amounts of revenues and expenses during the reporting period. Those estimates determined to be most critical to the preparation of the financial statements are discussed below in </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Note 2. Summary of Critical and Significant Accounting Policies — Critical Accounting Policies and Estimates.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> Actual results could differ from those estimates.</span></div>
CY2021	us-gaap	Use Of Estimates UseOfEstimates	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Use of Estimates —</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> The preparation of financial statements in conformity 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 financial statements and the reported amounts of revenues and expenses during the reporting period. Those estimates determined to be most critical to the preparation of the financial statements are discussed below in </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Note 2. Summary of Critical and Significant Accounting Policies — Critical Accounting Policies and Estimates.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> Actual results could differ from those estimates.</span>
CY2021Q4	us-gaap	Deferred Revenue DeferredRevenue	13300000	USD
CY2020Q4	us-gaap	Deferred Revenue DeferredRevenue	18400000	USD
CY2021	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Concentration of Credit Risk —</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%"> Financial instruments that potentially subject the Company to credit risks consist primarily of cash and cash equivalents and trade receivables. The Company places its cash and cash equivalents with high-quality financial institutions. Concentration of </span>credit risk with respect to accounts receivable for the Commercial Segment is limited because of the large number of clients and their dispersion across different industries and geographies, thus spreading the trade credit risk. The Company performs ongoing credit evaluations to identify risks and maintains an allowance to address these risks. Accounts receivables for the Federal Government Segment are primarily from the U.S. government and are considered to have low credit risk.
CY2021	us-gaap	Discontinued Operation Gain Loss From Disposal Of Discontinued Operation Before Income Tax DiscontinuedOperationGainLossFromDisposalOfDiscontinuedOperationBeforeIncomeTax	216900000	USD
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	26900000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	28100000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	27400000	USD
CY2021	us-gaap	Short Term Lease Cost ShortTermLeaseCost	5400000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	6400000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2000000.0	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	5100000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	5200000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	4600000	USD
CY2021	us-gaap	Lease Cost LeaseCost	37400000	USD
CY2020	us-gaap	Lease Cost LeaseCost	39700000	USD
CY2019	us-gaap	Lease Cost LeaseCost	34000000.0	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P3Y2M12D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P3Y8M12D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P4Y2M12D
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0347	Rate
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0386	Rate
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0404	Rate
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	29100000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	28100000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	26900000	USD
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	10800000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	18900000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	23500000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	25100000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	19900000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	12100000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	5900000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3300000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	800000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	67100000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	3600000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	63500000	USD
CY2021	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	3	business
CY2020	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	4	business
CY2019	us-gaap	Number Of Businesses Acquired NumberOfBusinessesAcquired	2	business
CY2021	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	221300000	USD
CY2020	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	186000000.0	USD
CY2019	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	113000000.0	USD
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	1291300000	USD
CY2020	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-100000	USD
CY2020Q4	us-gaap	Goodwill Gross GoodwillGross	1420700000	USD
CY2021	us-gaap	Goodwill Purchase Accounting Adjustments GoodwillPurchaseAccountingAdjustments	3300000	USD
CY2021	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-400000	USD
CY2021Q4	us-gaap	Goodwill Gross GoodwillGross	1569500000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	603600000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	358300000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	245300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	529800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	302500000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	227300000	USD
CY2021Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	242600000	USD
CY2021Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	242600000	USD
CY2020Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	242600000	USD
CY2020Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	242600000	USD
CY2021Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	846200000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	358300000	USD
CY2021Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	487900000	USD
CY2020Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	772400000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	302500000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	469900000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	54400000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	44500000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	35200000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	28700000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	25100000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	57400000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	245300000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	228800000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	206000000.0	USD
CY2021Q4	us-gaap	Property Plant And Equipment Other Accumulated Depreciation PropertyPlantAndEquipmentOtherAccumulatedDepreciation	173800000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Other Accumulated Depreciation PropertyPlantAndEquipmentOtherAccumulatedDepreciation	151100000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	55000000.0	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	54900000	USD
CY2021	us-gaap	Depreciation Depreciation	28000000.0	USD
CY2020	us-gaap	Depreciation Depreciation	28300000	USD
CY2019	us-gaap	Depreciation Depreciation	28000000.0	USD
CY2021Q4	us-gaap	Senior Notes SeniorNotes	550000000.0	USD
CY2020Q4	us-gaap	Senior Notes SeniorNotes	550000000.0	USD
CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1040800000	USD
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1040800000	USD
CY2021Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	6900000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	7400000	USD
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	1033900000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	1033400000	USD
CY2021Q4	asgn	Debt Covenant Maximum Senior Secured Debt To Ebitda Ratio DebtCovenantMaximumSeniorSecuredDebtToEBITDARatio	3.75
CY2021	asgn	Leverage Ratio LeverageRatio	1.02
CY2021	asgn	Disposal Group Including Discontinued Operations Net Sale Proceeds DisposalGroupIncludingDiscontinuedOperationsNetSaleProceeds	400000000	USD
CY2019Q4	us-gaap	Senior Notes SeniorNotes	550000000	USD
CY2021Q4	us-gaap	Purchase Obligation Due In Next Twelve Months PurchaseObligationDueInNextTwelveMonths	13700000	USD
CY2021Q4	us-gaap	Purchase Obligation Due In Second Year PurchaseObligationDueInSecondYear	8300000	USD
CY2021Q4	us-gaap	Purchase Obligation Due In Third Year PurchaseObligationDueInThirdYear	600000	USD
CY2021Q4	us-gaap	Purchase Obligation PurchaseObligation	22600000	USD
CY2021Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	2400000	USD
CY2020Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	2200000	USD
CY2021Q4	us-gaap	Estimated Insurance Recoveries EstimatedInsuranceRecoveries	10400000	USD
CY2020Q4	us-gaap	Estimated Insurance Recoveries EstimatedInsuranceRecoveries	10900000	USD
CY2021Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	4000000	USD
CY2021Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	15100000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	5000000	USD
CY2021	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	183300000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	27900000	USD
CY2021Q4	asgn	Stock Repurchase Program Term StockRepurchaseProgramTerm	P2Y
CY2021Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	350000000	USD
CY2021Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	335000000	USD
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	100000	shares
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	52700000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	32300000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	39300000	USD
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Accelerated Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardAcceleratedCompensationCost	10500000	USD
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2500000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1400000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	700000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	1100000	shares
CY2021Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber	1100000	shares
CY2021Q4	asgn	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested And Expected To Vest ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAndExpectedToVest	1100000	shares
CY2021	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y8M12D
CY2021Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	15600000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	14400000	USD
CY2021	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	19900000	USD
CY2020	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	15900000	USD
CY2019	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	15000000	USD
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	43600000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	44900000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	26000000.0	USD
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	15500000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	15500000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	7500000	USD
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	3000000.0	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1700000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1300000	USD
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	62100000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	62100000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	34800000	USD
CY2021	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	19500000	USD
CY2020	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	1800000	USD
CY2019	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	19900000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	81600000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	63900000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54700000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	304500000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	237600000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	199700000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	8900000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	3900000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	4700000	USD
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	313400000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	241500000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	204400000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	127500000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	145400000	USD
CY2021Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	11400000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	14300000	USD
CY2021Q4	asgn	Deferred Tax Liability Leasing Asset DeferredTaxLiabilityLeasingAsset	14800000	USD
CY2020Q4	asgn	Deferred Tax Liability Leasing Asset DeferredTaxLiabilityLeasingAsset	22100000	USD
CY2021Q4	asgn	Deferred Tax Assets Leasingliabilities DeferredTaxAssetsLeasingliabilities	15600000	USD
CY2020Q4	asgn	Deferred Tax Assets Leasingliabilities DeferredTaxAssetsLeasingliabilities	23300000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	1500000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	1400000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	20500000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	14800000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	10000000.0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	8400000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	10500000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	22500000	USD
CY2021Q4	asgn	Deferred Tax Assets Other Noncurrent DeferredTaxAssetsOtherNoncurrent	6600000	USD
CY2020Q4	asgn	Deferred Tax Assets Other Noncurrent DeferredTaxAssetsOtherNoncurrent	2900000	USD
CY2021Q4	asgn	Deferred Tax Liabilities Net Of Deferred Tax Assets And Valuation Allowance DeferredTaxLiabilitiesNetOfDeferredTaxAssetsAndValuationAllowance	89000000.0	USD
CY2020Q4	asgn	Deferred Tax Liabilities Net Of Deferred Tax Assets And Valuation Allowance DeferredTaxLiabilitiesNetOfDeferredTaxAssetsAndValuationAllowance	108500000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	65800000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	50700000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	42900000	USD
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	15200000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	12700000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	10600000	USD
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	3300000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	1300000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	1400000	USD
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	200000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	500000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	1300000	USD
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-2000000.0	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-1100000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-600000	USD
CY2021	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	3100000	USD
CY2021	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	231800000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2000000.0	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2500000	USD
CY2021	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	2200000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	1800000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	1600000	USD
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	81600000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	63900000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54700000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	0	USD
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	1300000	USD
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	71700000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	79600000	USD
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	160400000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	188100000	USD
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1300000	USD
CY2020	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	177600000	USD
CY2019	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	149700000	USD
CY2021	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	178100000	USD
CY2020	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	22700000	USD
CY2019	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	25000000.0	USD
CY2021	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	409900000	USD
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	200300000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	174700000	USD
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52800000	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	800000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	600000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	600000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53500000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53300000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53400000	shares
CY2021	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	4.40
CY2020	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	3.37
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.84
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	3.38
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.43
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.47
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.78
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.80
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.31
CY2021	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	4.33
CY2020	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	3.33
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.80
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	3.33
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.43
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.48
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.66
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.76
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.28
CY2021	us-gaap	Revenues Revenues	4009500000	USD
CY2020	us-gaap	Revenues Revenues	3502100000	USD
CY2019	us-gaap	Revenues Revenues	3415600000	USD
CY2021	us-gaap	Gross Profit GrossProfit	1142400000	USD
CY2020	us-gaap	Gross Profit GrossProfit	947200000	USD
CY2019	us-gaap	Gross Profit GrossProfit	971500000	USD
CY2021	us-gaap	Operating Income Loss OperatingIncomeLoss	350900000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	281200000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	276200000	USD
CY2021	us-gaap	Depreciation Depreciation	28000000.0	USD
CY2020	us-gaap	Adjustment For Amortization AdjustmentForAmortization	51000000.0	USD
CY2020	us-gaap	Depreciation Depreciation	28300000	USD
CY2019	us-gaap	Depreciation Depreciation	28000000.0	USD
CY2021	us-gaap	Adjustment For Amortization AdjustmentForAmortization	55700000	USD
CY2019	us-gaap	Adjustment For Amortization AdjustmentForAmortization	50300000	USD
CY2021	us-gaap	Revenues Revenues	4009500000	USD
CY2020	us-gaap	Revenues Revenues	3502100000	USD
CY2019	us-gaap	Revenues Revenues	3415600000	USD
CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1000000000	USD
CY2021Q4	us-gaap	Long Term Debt Fair Value LongTermDebtFairValue	1100000000	USD
CY2021Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	15100000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	5000000	USD
CY2021Q1	us-gaap	Revenues Revenues	907000000.0	USD
CY2021Q2	us-gaap	Revenues Revenues	974900000	USD
CY2021Q3	us-gaap	Revenues Revenues	1073800000	USD
CY2021Q4	us-gaap	Revenues Revenues	1053800000	USD
CY2021	us-gaap	Revenues Revenues	4009500000	USD
CY2021Q1	us-gaap	Gross Profit GrossProfit	243700000	USD
CY2021Q2	us-gaap	Gross Profit GrossProfit	276300000	USD
CY2021Q3	us-gaap	Gross Profit GrossProfit	308700000	USD
CY2021Q4	us-gaap	Gross Profit GrossProfit	313700000	USD
CY2021	us-gaap	Gross Profit GrossProfit	1142400000	USD
CY2021Q1	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	42800000	USD
CY2021Q2	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	57300000	USD
CY2021Q3	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	66300000	USD
CY2021Q4	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	65400000	USD
CY2021	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	231800000	USD
CY2021Q1	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	5900000	USD
CY2021Q2	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	6900000	USD
CY2021Q3	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	145700000	USD
CY2021Q4	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	19600000	USD
CY2021	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	178100000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	48700000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	64200000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	212000000.0	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.08
CY2021Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.26
CY2021Q4	us-gaap	Net Income Loss NetIncomeLoss	85000000.0	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	409900000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.81
CY2021Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.26
CY2021	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	4.40
CY2021Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.11
CY2021Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.13
CY2021Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	2.76
CY2021Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.38
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	3.38
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.92
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.21
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.02
CY2021Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.64
CY2021Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.06
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.78
CY2021Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.80
CY2021Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.24
CY2021Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.24
CY2021	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	4.33
CY2021Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.11
CY2021Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.13
CY2021Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	2.73
CY2021Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.38
CY2021	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	3.33
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.91
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.19
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.97
CY2021Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.62
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.66
CY2021Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	53000000.0	shares
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	53200000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2021Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52000000.0	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2021Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53700000	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53900000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53400000	shares
CY2021Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52900000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53500000	shares
CY2020Q1	us-gaap	Revenues Revenues	865400000	USD
CY2020Q2	us-gaap	Revenues Revenues	831900000	USD
CY2020Q3	us-gaap	Revenues Revenues	904400000	USD
CY2020Q4	us-gaap	Revenues Revenues	900400000	USD
CY2020	us-gaap	Revenues Revenues	3502100000	USD
CY2020Q1	us-gaap	Gross Profit GrossProfit	242600000	USD
CY2020Q2	us-gaap	Gross Profit GrossProfit	227500000	USD
CY2020Q3	us-gaap	Gross Profit GrossProfit	236300000	USD
CY2020Q4	us-gaap	Gross Profit GrossProfit	240800000	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.05
CY2020	us-gaap	Gross Profit GrossProfit	947200000	USD
CY2020Q1	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	39100000	USD
CY2020Q2	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	43500000	USD
CY2020Q3	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	46700000	USD
CY2020Q4	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	48300000	USD
CY2020	asgn	Net Income From Continuing Operations NetIncomeFromContinuingOperations	177600000	USD
CY2020Q1	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	4700000	USD
CY2020Q2	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	5300000	USD
CY2020Q3	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	5600000	USD
CY2020Q4	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	7100000	USD
CY2020	asgn	Net Income From Discontinued Operations NetIncomeFromDiscontinuedOperations	22700000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	43800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	48800000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	52300000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	55400000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	200300000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.74
CY2020Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.83
CY2020Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.89
CY2020Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.91
CY2020	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	3.37
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.09
CY2020Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.10
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.11
CY2020Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.14
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic And Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShare	0.43
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.83
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.93
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.00
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.80
CY2020Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.73
CY2020Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.82
CY2020Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.88
CY2020Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.90
CY2020	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	3.33
CY2020Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.09
CY2020Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.10
CY2020Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.11
CY2020Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.14
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.43
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.82
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.92
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.99
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.04
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.76
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52500000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52500000	shares
CY2020Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52800000	shares
CY2020Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52800000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52700000	shares
CY2020Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53300000	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53000000.0	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53000000.0	shares
CY2020Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53500000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53300000	shares
CY2021	dei	Auditor Firm AuditorFirmId	34

Files In Submission

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$ASGN
ASGN Inc Stock $asgn

2021 Q4 Form 10-K Financial Statement

#000089056422000007 Filed on March 01, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ASGN ASGN Inc Stock $asgn

2021 Q4 Form 10-K Financial Statement

#000089056422000007 Filed on March 01, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ASGN
ASGN Inc Stock $asgn