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v2.4.1.9

Commitments and Contingencies (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Commitment and contingencies [Line Items] |  |  |
Deferred Rent Credit, Current | $ 300,000 us-gaap_DeferredRentCreditCurrent |  |
Long-term Debt |  |  |
2013 | 18,250,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths |  |
2014 | 18,250,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo |  |
2015 | 18,250,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree |  |
2016 | 180,063,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour |  |
2017 | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive |  |
Thereafter | 180,312,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive |  |
Total | 415,125,000 us-gaap_LongTermDebt |  |
Operating Leases |  |  |
2013 | 15,012,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent |  |
2014 | 12,809,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears |  |
2015 | 9,871,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears |  |
2016 | 8,015,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears |  |
2017 | 5,796,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears |  |
Thereafter | 8,516,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter |  |
Total | 60,019,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDue |  |
Related Party |  |  |
2013 | 1,066,000 us-gaap_OtherCommitmentDueInNextTwelveMonths |  |
2014 | 1,190,000 us-gaap_OtherCommitmentDueInSecondYear |  |
2015 | 1,169,000 us-gaap_OtherCommitmentDueInThirdYear |  |
2016 | 1,302,000 us-gaap_OtherCommitmentDueInFourthYear |  |
2017 | 1,282,000 us-gaap_OtherCommitmentDueInFifthYear |  |
Thereafter | 6,659,000 us-gaap_OtherCommitmentDueAfterFifthYear |  |
Total | 12,668,000 us-gaap_OtherCommitment |  |
Total |  |  |
2013 | 16,078,000 us-gaap_ContractualObligationDueInNextTwelveMonths |  |
2014 | 13,999,000 us-gaap_ContractualObligationDueInSecondYear |  |
2015 | 11,040,000 us-gaap_ContractualObligationDueInThirdYear |  |
2016 | 9,317,000 us-gaap_ContractualObligationDueInFourthYear |  |
2017 | 7,078,000 us-gaap_ContractualObligationDueInFifthYear |  |
Thereafter | 15,175,000 us-gaap_ContractualObligationDueAfterFifthYear |  |
Total | 72,687,000 us-gaap_ContractualObligation |  |
Deferred rent liability, noncurrent | 4,000,000 us-gaap_DeferredRentCreditNoncurrent | 3,400,000 us-gaap_DeferredRentCreditNoncurrent |
Rent expense | 17,600,000 us-gaap_LeaseAndRentalExpense | 15,400,000 us-gaap_LeaseAndRentalExpense | 11,400,000 us-gaap_LeaseAndRentalExpense
Self Insurance Reserve | 2,200,000 us-gaap_SelfInsuranceReserve | 2,700,000 us-gaap_SelfInsuranceReserve |
Workers' Compensation and Medical Malpractice Receivable, Current | 13,370,000 asgn_WorkersCompensationandMedicalMalpracticeReceivableCurrent | 14,390,000 asgn_WorkersCompensationandMedicalMalpracticeReceivableCurrent |
Letters of credit outstanding | 3,200,000 us-gaap_LettersOfCreditOutstandingAmount | 2,700,000 us-gaap_LettersOfCreditOutstandingAmount |
contingent consideration maximum | 11,000,000 asgn_Contingentconsiderationmaximum |  |
Income tax reserve in other long-term liabilities | 900,000 us-gaap_LiabilityForUncertainTaxPositionsNoncurrent |  |
Other Liabilities, Current | $ 20,729,000 us-gaap_OtherLiabilitiesCurrent | $ 26,460,000 us-gaap_OtherLiabilitiesCurrent |
Apex Systems |  |  |
Total |  |  |
Number of leased properties owned by related parties (in number of properties) | 2 asgn_NumberOfLeasedPropertiesOwnedByRelatedParties / us-gaap_BusinessAcquisitionAxis = asgn_ApexSystemsMember |  |

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