3.25.2 html 159 189 1 false 31 0 false 5 false false R1.htm 0000001 - Document - Document and Entity Information Sheet http://www.onassignment.com/role/DocumentandEntityInformation Document and Entity Information Cover 1 false false R2.htm 9952151 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS Sheet http://www.onassignment.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS CONDENSED CONSOLIDATED BALANCE SHEETS Statements 2 false false R3.htm 9952152 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) Sheet http://www.onassignment.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSParenthetical CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) Statements 3 false false R4.htm 9952153 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME Sheet http://www.onassignment.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOME CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME Statements 4 false false R5.htm 9952154 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY Sheet http://www.onassignment.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY Statements 5 false false R6.htm 9952155 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS Sheet http://www.onassignment.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS Statements 6 false false R7.htm 9952156 - Disclosure - General Sheet http://www.onassignment.com/role/General General Notes 7 false false R8.htm 9952157 - Disclosure - Balance Sheet Details Sheet http://www.onassignment.com/role/BalanceSheetDetails Balance Sheet Details Notes 8 false false R9.htm 9952158 - Disclosure - Acquisitions Sheet http://www.onassignment.com/role/Acquisitions Acquisitions Notes 9 false false R10.htm 9952159 - Disclosure - Goodwill and Identifiable Assets Sheet http://www.onassignment.com/role/GoodwillandIdentifiableAssets Goodwill and Identifiable Assets Notes 10 false false R11.htm 9952160 - Disclosure - Long-Term Debt Sheet http://www.onassignment.com/role/LongTermDebt Long-Term Debt Notes 11 false false R12.htm 9952161 - Disclosure - Commitments and Contingencies Sheet http://www.onassignment.com/role/CommitmentsandContingencies Commitments and Contingencies Notes 12 false false R13.htm 9952162 - Disclosure - Income Taxes Sheet http://www.onassignment.com/role/IncomeTaxes Income Taxes Notes 13 false false R14.htm 9952163 - Disclosure - Earnings Per Share Sheet http://www.onassignment.com/role/EarningsPerShare Earnings Per Share Notes 14 false false R15.htm 9952164 - Disclosure - Segment Reporting Sheet http://www.onassignment.com/role/SegmentReporting Segment Reporting Notes 15 false false R16.htm 9952165 - Disclosure - Fair Value Measurements Sheet http://www.onassignment.com/role/FairValueMeasurements Fair Value Measurements Notes 16 false false R17.htm 995410 - Disclosure - Pay vs Performance Disclosure Sheet http://xbrl.sec.gov/ecd/role/PvpDisclosure Pay vs Performance Disclosure Notes 17 false false R18.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 18 false false R19.htm 9955511 - Disclosure - Balance Sheet Details (Tables) Sheet http://www.onassignment.com/role/BalanceSheetDetailsTables Balance Sheet Details (Tables) Tables http://www.onassignment.com/role/BalanceSheetDetails 19 false false R20.htm 9955512 - Disclosure - Acquisitions (Tables) Sheet http://www.onassignment.com/role/AcquisitionsTables Acquisitions (Tables) Tables http://www.onassignment.com/role/Acquisitions 20 false false R21.htm 9955513 - Disclosure - Goodwill and Identifiable Assets (Tables) Sheet http://www.onassignment.com/role/GoodwillandIdentifiableAssetsTables Goodwill and Identifiable Assets (Tables) Tables http://www.onassignment.com/role/GoodwillandIdentifiableAssets 21 false false R22.htm 9955514 - Disclosure - Long-Term Debt (Tables) Sheet http://www.onassignment.com/role/LongTermDebtTables Long-Term Debt (Tables) Tables http://www.onassignment.com/role/LongTermDebt 22 false false R23.htm 9955515 - Disclosure - Earnings Per Share (Tables) Sheet http://www.onassignment.com/role/EarningsPerShareTables Earnings Per Share (Tables) Tables http://www.onassignment.com/role/EarningsPerShare 23 false false R24.htm 9955516 - Disclosure - Segment Reporting (Tables) Sheet http://www.onassignment.com/role/SegmentReportingTables Segment Reporting (Tables) Tables http://www.onassignment.com/role/SegmentReporting 24 false false R25.htm 9955517 - Disclosure - Balance Sheet Details (Details) Sheet http://www.onassignment.com/role/BalanceSheetDetailsDetails Balance Sheet Details (Details) Details http://www.onassignment.com/role/BalanceSheetDetailsTables 25 false false R26.htm 9955518 - Disclosure - Acquisitions - Additional Information (Details) Sheet http://www.onassignment.com/role/AcquisitionsAdditionalInformationDetails Acquisitions - Additional Information (Details) Details 26 false false R27.htm 9955519 - Disclosure - Goodwill and Identifiable Assets (Goodwill) (Details) Sheet http://www.onassignment.com/role/GoodwillandIdentifiableAssetsGoodwillDetails Goodwill and Identifiable Assets (Goodwill) (Details) Details http://www.onassignment.com/role/GoodwillandIdentifiableAssetsTables 27 false false R28.htm 9955520 - Disclosure - Goodwill and Identifiable Assets (Acquired Intangible Assets) (Details) Sheet http://www.onassignment.com/role/GoodwillandIdentifiableAssetsAcquiredIntangibleAssetsDetails Goodwill and Identifiable Assets (Acquired Intangible Assets) (Details) Details http://www.onassignment.com/role/GoodwillandIdentifiableAssetsTables 28 false false R29.htm 9955521 - Disclosure - Goodwill and Identifiable Assets (Future Amortization Expense) (Details) Sheet http://www.onassignment.com/role/GoodwillandIdentifiableAssetsFutureAmortizationExpenseDetails Goodwill and Identifiable Assets (Future Amortization Expense) (Details) Details http://www.onassignment.com/role/GoodwillandIdentifiableAssetsTables 29 false false R30.htm 9955522 - Disclosure - Long-Term Debt - Schedule of Debt (Details) Sheet http://www.onassignment.com/role/LongTermDebtScheduleofDebtDetails Long-Term Debt - Schedule of Debt (Details) Details 30 false false R31.htm 9955523 - Disclosure - Long-term Debt - Narrative (Details) Sheet http://www.onassignment.com/role/LongtermDebtNarrativeDetails Long-term Debt - Narrative (Details) Details 31 false false R32.htm 9955524 - Disclosure - Earnings Per Share (Calculation of Basic and Diluted Earnings per Share) (Details) Sheet http://www.onassignment.com/role/EarningsPerShareCalculationofBasicandDilutedEarningsperShareDetails Earnings Per Share (Calculation of Basic and Diluted Earnings per Share) (Details) Details http://www.onassignment.com/role/EarningsPerShareTables 32 false false R33.htm 9955525 - Disclosure - Segment Reporting - Narrative (Details) Sheet http://www.onassignment.com/role/SegmentReportingNarrativeDetails Segment Reporting - Narrative (Details) Details 33 false false R34.htm 9955526 - Disclosure - Segment Reporting - Segment Reporting Information (Details) Sheet http://www.onassignment.com/role/SegmentReportingSegmentReportingInformationDetails Segment Reporting - Segment Reporting Information (Details) Details 34 false false R35.htm 9955527 - Disclosure - Segment Reporting - Revenue by Customer Type (Details) Sheet http://www.onassignment.com/role/SegmentReportingRevenuebyCustomerTypeDetails Segment Reporting - Revenue by Customer Type (Details) Details 35 false false R36.htm 9955528 - Disclosure - Fair Value Measurements - Narrative (Details) Sheet http://www.onassignment.com/role/FairValueMeasurementsNarrativeDetails Fair Value Measurements - Narrative (Details) Details 36 false false All Reports Book All Reports asgn-20250630.htm asgn-20250630.xsd asgn-20250630_cal.xml asgn-20250630_def.xml asgn-20250630_lab.xml asgn-20250630_pre.xml http://fasb.org/us-gaap/2025 http://xbrl.sec.gov/dei/2025 http://xbrl.sec.gov/ecd/2025 true true