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Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Level 3 Fair Value, Inputs, Level 3 [Member] Contract with customer, asset Contract with Customer, Asset, before Allowance for Credit Loss Leases Lessee, Leases [Policy Text Block] Revolving Line of Credit Line of Credit [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Deferred tax liabilities Other long-term liabilities Deferred Income Tax Liabilities, Net Intangible Assets, Net Intangibles, net of accumulated amortization Intangible Assets, Net (Excluding Goodwill) Proceeds from company-owned life insurance Proceeds from Life Insurance Policy Earnings (loss) from operations Earnings (loss) from operations Operating Income (Loss) Severance Costs Severance Costs Impairment of Long-Lived Assets, Intangible Assets, Equity Method Investments and Equity Securities Impairment or Disposal of Long-Lived Assets, Including Intangible Assets, Policy [Policy Text Block] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Commitments and contingencies (See Commitments and Contingencies footnotes) Commitments and Contingencies Financing: Lessee, Finance Lease, Description [Abstract] Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Increase (decrease) in operating lease liabilities Increase (Decrease) in Operating Lease Liabilities Increase (Decrease) in Operating Lease Liabilities Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Income and other taxes Taxes Payable, Current Entity Address, State or Province Entity Address, State or Province Vested (in shares) Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Income tax based on statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Earnings invested in the business Retained Earnings (Accumulated Deficit) Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Other Assets Other Assets Disclosure [Text Block] Depreciation and amortization Deferred Tax Liabilities, Property, Plant and Equipment Accounting Standards Update 2016-01 Accounting Standards Update 2016-01 [Member] Money market funds Money Market Funds, at Carrying Value Currency exchange effects Accounts Receivable, Allowance for Credit Loss, Current Exchange Effects Accounts Receivable, Allowance for Credit Loss, Current Exchange Effects 2021 Finance Lease, Liability, to be Paid, Year One Property and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Income Taxes Income Tax, Policy [Policy Text Block] Total lease cost Lease, Cost Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Education Education [Member] Education [Member] Other investing activities Payments for (Proceeds from) Other Investing Activities Difference between Revenue Guidance in Effect before and after Topic 606 Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Revenue from services Revenue from Contract with Customer, Excluding Assessed Tax Advertising expense Advertising Expense NextGen Global Resources LLC NextGen Global Resources LLC [Member] NextGen Global Resources LLC [Member] Business Acquisition [Axis] Business Acquisition [Axis] Capitalized contract cost, amortization Capitalized Contract Cost, Amortization Geographical [Domain] Geographical [Domain] Talent Solutions Talent Solutions [Member] Talent Solutions [Member] Lease Termination Costs Gain (Loss) on Termination of Lease Foreign Deferred Foreign Income Tax Expense (Benefit) Noncurrent liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Entity Voluntary Filers Entity Voluntary Filers Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Credit Facility [Axis] Credit Facility [Axis] Liability for nonqualified plans Deferred Compensation Liability, Current and Noncurrent Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Business Combinations [Abstract] Business Combinations [Abstract] Pro forma information, earnings or loss of acquiree since acquisition date, actual Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Tax law change Tax Law Change The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to changes in the enacted income tax laws in the period. 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Schedule, 12-09, Valuation Allowances and Reserves, Deduction Other comprehensive income (loss) before classifications OCI, before Reclassifications, Net of Tax, Attributable to Parent Number of Countries in which Entity Operates Number of Countries in which Entity Operates Total Asia-Pacific Region Asia Pacific Asia Pacific [Member] City Area Code City Area Code Book overdrafts Book Overdrafts [Member] Represents outstanding checks in excess of funds on deposit that are reclassified to a liability. ROU Liabilities: Lease Liabilities [Abstract] Lease Liabilities Document Period End Date Document Period End Date Accrued workers' compensation and other claims Workers' Compensation Liability, Current Schedule of lease terms and discount rates Schedule of Lease Terms and Discount Rates [Table Text Block] Schedule of Lease Terms and Discount Rates Advances to PersolKelly Asia Pacific Advances to Affiliate Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] 2018 grant 2018 grant [Member] 2018 grant [Member] Accrued payroll and related taxes Employee-related Liabilities Equity securities, FV-NI and without readily determinable fair value Equity Securities, FV-NI and without Readily Determinable Fair Value Stock-based compensation Share-based Payment Arrangement, Noncash Expense Net change in short-term borrowings Proceeds from (Repayments of) Short-term Debt Capital expenditures Payments to Acquire Productive Assets Nature of Expense [Axis] Nature of Expense [Axis] Fiscal period duration Fiscal Period Duration Other financing activities Proceeds from (Payments for) Other Financing Activities Kenzie Academy Inc. Kenzie Academy Inc. [Member] Kenzie Academy Inc. 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Repayment of loan Repayment of Notes Receivable from Related Parties Sale of Main Headquarters Sale of Main Headquarters [Member] Sale of Main Headquarters Assets acquired net of liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Grants in period (in dollars per share) Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Short-term borrowings Short-term Debt Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] (Increase) decrease in trade accounts receivable Increase (Decrease) in Accounts Receivable Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Lease expense Operating Leases, Rent Expense, Net Total Liabilities and Stockholders' Equity Liabilities and Equity Loss Contingencies [Line Items] Loss Contingencies [Line Items] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Income Taxes Income Tax Disclosure [Text Block] Total noncurrent liabilities Liabilities, Noncurrent Reductions for expiration of statutes Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Operating lease cost Operating Lease, Cost Undistributed earnings of foreign subsidiaries Undistributed Earnings of Foreign Subsidiaries Total current Current Income Tax Expense (Benefit) Financing lease, weighted average remaining lease term (years) Finance Lease, Weighted Average Remaining Lease Term Other, net Other Noncash Income (Expense) Additions for prior years’ tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Workers' Compensation Workers Compensation Policy [Policy Text Block] Disclosure of accounting policy for establishing accruals for workers' compensation claims. Finite-lived intangible asset, useful life Finite-Lived Intangible Asset, Useful Life Equity Component [Domain] Equity Component [Domain] Gross profit Gross profit Gross Profit Net property and equipment Property, Plant and Equipment, Net Entity Tax Identification Number Entity Tax Identification Number Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Accrued retirement benefits Deferred Compensation Liability, Classified, Noncurrent Stock-Based Compensation Share-based Payment Arrangement [Text Block] Net earnings (loss) Net earnings (loss) Net earnings (loss) Net Income (Loss) Attributable to Parent Pro Forma Pro Forma [Member] Current period provision Financing Receivable, Credit Loss, Expense (Reversal) Outcome-Based Services Outcome-Based Services [Member] Outcome-Based Services [Member] Business combination, net earnings reported by acquired entity for prior period Business Combination, Net Earnings Reported by Acquired Entity for Prior Period Business Combination, Net Earnings Reported by Acquired Entity for Prior Period Trade Names Trade Names [Member] Summary of Significant Accounting Policies Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Sale of Assets [Abstract] Sale of Assets Current Fiscal Year End Date Current Fiscal Year End Date Total Finance Lease, Liability Currency exchange effects SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment Other income Other Nonoperating Income Intangible assets acquired Intangibles Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Credit carryforwards Deferred Tax Assets, Tax Credit Carryforwards Other information related to leases Other Information Related to Leases [Table Text Block] Other Information Related to Leases Brazil indemnification Indemnification, Fair Value Disclosure Indemnification, Fair Value Disclosure Thereafter Finance Lease, Liability, to be Paid, after Year Five Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Real Estate Held-for-sale Real Estate Held-for-sale Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Operating lease asset amortization Operating Lease, Right-of-Use Asset, Amortization Operating Lease, Right-of-Use Asset, Amortization Allowance for doubtful accounts SEC Schedule, 12-09, Allowance, Credit Loss [Member] Property and Equipment at Cost and Depreciable Useful Lives Property, Plant and Equipment [Table Text Block] Remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Gross Carrying amount Finite-Lived Intangible Assets, Gross Provision for credit losses and sales allowances Accounts Receivable, Credit Loss Expense (Reversal) Proceeds (payments) related to loans to equity affiliate Proceeds from (Repayments of) Related Party Debt Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net earnings before equity in net earnings (loss) of affiliate Income (Loss) from Continuing Operations Before Equity Method Investments Amount of income (loss) from continuing operations before addition of income (loss) from equity method investments. Related Party Transactions [Abstract] Related Party Transactions [Abstract] Finance lease, right-of-use assets Finance Lease, Right-of-Use Asset, after Accumulated Amortization Maturities of operating lease liabilities under ASC 842 Lessee, Operating Lease, Liability, Maturity [Table Text Block] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Document Information [Line Items] Document Information [Line Items] Capital stock, $1.00 par value Capital stock, $1.00 par value [Abstract] Capital stock, $1.00 par value [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Revenue Revenue from Contract with Customer [Text Block] Equity method investment, ownership percentage Equity Method Investment, Ownership Percentage ROU assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Performance measurement period Share-based Compensation Arrangement by Share-based Payment Award, Performance Measurement Period Share-based Compensation Arrangement by Share-based Payment Award, Performance Measurement Period Cash and Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Foreign exchange gains (losses) Foreign Currency Transaction Gain (Loss), before Tax Income tax expense (benefit) Total provision Income tax expense (benefit) Income Tax Expense (Benefit) Cash, cash equivalents and restricted cash at beginning of year Cash, cash equivalents and restricted cash at end of year Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Income Taxes [Line Items] Income Taxes [Line Items] [Line Items] for Income Taxes [Table] Finance lease current liabilities Finance Lease, Liability, Current Local Phone Number Local Phone Number Tax-free earnings (loss) included in SG&A expenses Earnings Losses on Value of Deferred Compensation Assets Earnings (losses) on the value of the deferred compensation assets. Purchase price paid at closing Payments to Acquire Businesses, Gross Business Acquisition, Pro Forma Information Business Acquisition, Pro Forma Information [Table Text Block] Total Americas Region Americas Americas [Member] Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Domain] Pro forma information, revenue of acquiree since acquisition date, actual Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Interim Period, Costs Not Allocable [Domain] Interim Period, Costs Not Allocable [Domain] Schedule of Indefinite-Lived Intangible Assets Schedule of Indefinite-Lived Intangible Assets [Table Text Block] Indefinite-lived Intangible Assets [Roll Forward] Indefinite-lived Intangible Assets [Roll Forward] Reductions for prior years’ tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Accounting Standards Update 2018-15 Accounting Standards Update 2018-15 [Member] Deferred revenue Contract with Customer, Liability Schedule II - Valuation Reserves SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Award Type [Axis] Award Type [Axis] Weighted Average Grant Date Fair Value Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Prepaid Expenses and Other Current Assets Prepaid Expenses and Other Current Assets [Member] Vested in period, fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Other noncurrent assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Net cash from (used in) investing activities Net Cash Provided by (Used in) Investing Activities Investment in equity securities Payments to Acquire Investments Equity Award [Domain] Award Type [Domain] Noncurrent Liabilities Liabilities, Noncurrent [Abstract] Financing Receivable, Allowance for Credit Loss Financing Receivable, Allowance for Credit Loss [Table Text Block] Summary of Restructuring Reserve Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Gain (Loss) on Securities [Line Items] Gain (Loss) on Securities [Line Items] Treasury stock, value Treasury Stock, Value Earnings Per Share Earnings Per Share [Text Block] Current Liabilities Liabilities, Current [Abstract] U.S. statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Terence E. Adderley Revocable Trust K Terence E. Adderley Revocable Trust K [Member] Terence E. Adderley Revocable Trust K [Member] Asset Impairment Charges Asset Impairment Charges [Text Block] New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Subsegments [Axis] Subsegments [Axis]