Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Earnings Per Share [Abstract] Calculations of net earnings per share basic and diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Equity [Abstract] Components of Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Defined benefit pension plans, net of income taxes of $(27.6) and $(27.8), respectively Pension Plan [Member] Retiree health care plan, net of income taxes of $1.9 and $2.0, respectively Postretirement Health Coverage [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Foreign currency translation Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Translation loss on net investment hedge, net of income taxes of $(17.3) and $(23.1), respectively Derivatives used in Net Investment Hedge, Net of Tax Translation loss on long-term intercompany loans Intercompany Foreign Currency Balance, Amount Unrealized gain on investments, net of income taxes of $3.4 for 2017 Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Defined benefit plans Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income translation gain (loss) on net investment hedge, tax Accumulated Other Comprehensive Income Translation Gain Loss on Net Investment Hedge, Tax Tax effect of current period adjustment resulting from gains and losses on foreign currency transactions that are designated as, and are effective as, economic hedges of a net investment in a foreign entity. Unrealized gain (loss) on investments, tax Unrealized Gain (Loss) on Investments, Tax Unrealized Gain (Loss) on Investments, Tax Pension and other postretirement benefit plans, accumulated other comprehensive income (loss), tax Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Tax Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Tax Reclassification of unrealized cumulative gain on investments Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Equity Method, after Tax Schedule of Indefinite-lived Intangible Assets by Major Class [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Customer relationships Customer Relationships [Member] Other Other Intangible Assets [Member] Indefinite-lived Intangible Assets by Major Class [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Tradenames Trade Names [Member] Reacquired franchise rights Reacquired Franchise Rights [Member] The rights we reacquired through business combinations that we had previously granted to the franchisees (acquirees) to use our trade name under a franchise agreement. Prior to 2009, these rights were considered indefinite-lived. Goodwill [Line Items] Goodwill [Line Items] Goodwill Goodwill Finite-lived: Finite-Lived Intangible Assets, Net [Abstract] Gross Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Net Finite-Lived Intangible Assets, Net Indefinite-lived: Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] Gross Indefinite Lived Intangible Assets (Excluding Goodwill), Gross Sum of the gross amounts (original costs for current and prior period additions adjusted for impairment, if any) as of the balance sheet date of intangible assets, excluding goodwill, having a projected indefinite period of benefit. Net Indefinite-Lived Intangible Assets (Excluding Goodwill) Accumulated impairment loss Indefinite Lived Intangible Assets (Excluding Goodwill), Impaired, Accumulated Impairment Loss The accumulated impairment losses related to indefinite-lived intangible assets (excluding goodwill) as of the balance sheet date. Total intangible assets Intangible Assets, Net (Excluding Goodwill) [Abstract] Gross Intangible Assets, Gross (Excluding Goodwill) Accumulated Amortization Intangible Assets, Accumulated Amortization (Excluding Goodwill), Total Intangible Assets, Accumulated Amortization (Excluding Goodwill), Total. Net Intangible Assets, Net (Excluding Goodwill) Accumulated impairment loss Goodwill, Impaired, Accumulated Impairment Loss Intangible Assets, Future Amortization Expense by Fiscal Year [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Estimated amortization expense, remainder of 2018 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Estimated amortization expense, 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two Estimated amortization expense, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three Estimated amortization expense, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four Estimated amortization expense, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five Estimated amortization expense, 2023 Finite-Lived Intangible Assets, Amortization Expense, after Year Five Class of Treasury Stock [Table] Class of Treasury Stock [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Common Stock Repurchase 2018 Authorization Common Stock Repurchase 2018 Authorization [Member] Common Stock Repurchase 2018 Authorization 2016 Authorization Common Stock Repurchase 2016 Authorization [Member] Common Stock Repurchase 2016 Authorization Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Shares authorized to be repurchased (in shares) Stock Repurchase Program, Number of Shares Authorized to be Repurchased Shares repurchased during period (in shares) Treasury Stock, Shares, Acquired Total cost of shares repurchased Payments for Repurchase of Common Stock Shares remaining authorized for repurchase (in shares) Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased Accounting Policies [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] United States UNITED STATES Germany GERMANY Netherlands Netherlands [Member] The name of a geographic segment representing facts about a reporting entity disaggregated by the geographic area of the entities activities. United Kingdom UNITED KINGDOM France FRANCE Right Management Right Management [Member] Segment information pertaining to Right Management. Other reporting units Other Segments [Member] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Share-based compensation expense Share-based Compensation Consideration received from share-based awards Sale of Stock, Consideration Received on Transaction Basis of Presentation and Accounting Policies Significant Accounting Policies [Text Block] Retirement Benefits [Abstract] Components of net periodic benefit cost Schedule of Net Benefit Costs [Table Text Block] Income Tax Disclosure [Abstract] Effective income tax rate (as percent) Effective Income Tax Rate Reconciliation, Percent U.S. Federal statutory rate (as percent) Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Income Tax [Table] Income Tax [Table] Income Tax [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Income Tax [Line Items] Income Tax [Line Items] [Line Items] for Income Tax [Table] Expected annual effective income tax rate (as percent) Expected Annual Effective Income Tax Rate Continuing Operations Expected Annual Effective Income Tax Rate Pertaining to Continuing Operations Tax Cuts and Jobs Act of 2017, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense (Benefit) Tax Cuts and Jobs Act of 2017, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense (Benefit) Tax Cuts and Jobs Act of 2017, Transition Tax for Accumulated Foreign Earnings, Income Tax Expense (Benefit) Gross unrecognized tax benefits, including interest and penalties Unrecognized Tax Benefits Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Financial Instruments and Fair Value Measurements Derivative Instruments and Hedging Activities Disclosure [Text Block] Document and Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Transferred over time Transferred over Time [Member] Transferred at point in time Transferred at Point in Time [Member] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Staffing and Interim Staffing and Interim [Member] Staffing and Interim [Member] Outcome-Based Solutions and Consulting Outcome-Based Solutions and Consulting [Member] Outcome-Based Solutions and Consulting [Member] Permanent Recruitment Permanent Recruitment [Member] Permanent Recruitment [Member] Products and Services, Other Products and Services, Other [Member] Products and Services, Other [Member] Americas Americas [Member] Southern Europe Southern Europe [Member] Segment information pertaining to Southern Europe. Northern Europe Northern Europe [Member] Segment information pertaining to Northern Europe. APME APME [Member] Segment information pertaining to APME. Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Revenue from Contract with Customer, Excluding Assessed Tax Revenue from Contract with Customer, Excluding Assessed Tax Income Statement [Abstract] Revenues from services Sales Revenue, Services, Net Cost of services Cost of Services Gross profit Gross Profit Selling and administrative expenses Selling, General and Administrative Expense Operating profit Operating Income (Loss) Interest and other expenses Interest And Other Nonoperating Expenses Sum of interest income and expense, foreign exchange gains and losses and other miscellaneous non-operating income and expenses. Earnings before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net earnings Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net earnings per share - basic (in dollars per share) Earnings Per Share, Basic Net earnings per share - diluted (in dollars per share) Earnings Per Share, Diluted Weighted average shares - basic (in shares) Weighted Average Number of Shares Outstanding, Basic Weighted average shares - diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Restructuring and Related Activities [Abstract] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Reportable segments Operating Segments [Member] Corporate Corporate, Non-Segment [Member] Americas Americas Segment [Member] Americas Segment [Member] Subsegments [Axis] Subsegments [Axis] Subsegments [Domain] Subsegments [Domain] United States United States Subsegment [Member] United States Subsegment [Member] France France Subsegment [Member] France Subsegment [Member] Italy Italy Subsegment [Member] Italy Subsegment [Member] Subsegments Consolidation Items [Axis] Subsegments Consolidation Items [Axis] Subsegments Consolidation Items [Domain] Subsegments Consolidation Items [Domain] Reportable subsegments Reportable Subsegments [Member] Restructuring Cost [Abstract] Restructuring Cost and Reserve [Line Items] Net restructuring costs Restructuring Charges Restructuring reserve [Roll Forward] Restructuring Reserve [Roll Forward] Balance, beginning of period Restructuring Reserve Severance Costs Severance Costs Office closure costs and other Business Exit Costs Costs paid or utilized Payments for Restructuring Balance, end of period Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Notes due September 2022 Notes Due September 2022 [Member] Notes Due September 2022 [Member] Notes due June 2018 Notes Due June 2018 [Member] Notes Due June 2018 [Member] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value, Disclosure Item Amounts [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Fair value Estimate of Fair Value Measurement [Member] Carrying value Reported Value Measurement [Member] Derivative, by Nature [Axis] Derivative Instrument [Axis] Derivative, Name [Domain] Derivative Contract [Domain] Euro-denominated notes Euro denominated Notes [Member] An obligation resulting from borrowing money. Forward contracts Forward Contracts [Member] Fair Value by Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair value measured on a recurring basis Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Designated as hedging instrument Designated as Hedging Instrument [Member] Not designated as hedging instrument Not Designated as Hedging Instrument [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Net investment hedges [Abstract] Summary of Net Investment Hedge Activity [Abstract] Long-term debt Debt Instrument, Face Amount Translation gain (loss) on net investment hedge Gain associated with forward contracts included in interest and other expenses Derivative, Gain on Derivative Assets Assets [Abstract] Deferred compensation plan assets Deferred Compensation Plan Assets Foreign currency forward contracts Foreign Currency Contract, Asset, Fair Value Disclosure Total assets measured at fair value Assets, Fair Value Disclosure Liabilities Liabilities [Abstract] Foreign currency forward contracts Foreign Currency Contracts, Liability, Fair Value Disclosure Total liabilities measured at fair value Financial Liabilities Fair Value Disclosure Carrying value of long-term debt Notes Payable, Fair Value Disclosure Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Net earnings Adjustments to reconcile net earnings to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Deferred income taxes Deferred Income Taxes and Tax Credits Provision for doubtful accounts Provision for Doubtful Accounts Share-based compensation Changes in operating assets and liabilities, excluding the impact of acquisitions: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Other assets Increase (Decrease) in Other Operating Assets Other liabilities Increase (Decrease) in Other Operating Liabilities Cash provided by operating activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Capital expenditures Payments to Acquire Productive Assets Acquisitions of businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Proceeds from the sale of investments, property and equipment Proceeds from Sale of Property, Plant, and Equipment Cash used in investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Net change in short-term borrowings Proceeds from (Repayments of) Short-term Debt Proceeds from long-term debt Proceeds from Issuance of Long-term Debt Repayments of long-term debt Repayments of Long-term Debt Payments of debt issuance costs Payments of Debt Issuance Costs Payments of contingent consideration for acquisitions Payment for Contingent Consideration Liability, Financing Activities Proceeds from share-based awards and other equity transactions Proceeds From Share-Based Awards And Other Equity Transactions Cash received on stock transaction after deduction of issuance costs, and on other equity transactions. Payments to noncontrolling interests Payments to Noncontrolling Interests Other share-based award transactions Other Share Based Award Transactions Net The total cash inflow (outflow) associated with share-based award transactions not individually reported. Repurchases of common stock Dividends paid Payments of Dividends Cash used in financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations Effect of exchange rate changes on cash Effect of Exchange Rate on Cash and Cash Equivalents Change in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of year Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period SUPPLEMENTAL CASH FLOW INFORMATION: Supplemental Cash Flow Information [Abstract] Interest paid Interest Paid, Net Income taxes paid, net Income Taxes Paid, Net Debt Disclosure [Abstract] Debt Debt Disclosure [Text Block] New Accounting Pronouncements and Changes in Accounting Principles [Abstract] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Text Block] Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Stock Options Employee Stock Option [Member] Non-Stock Option Awards Non-Stock Option Awards [Member] Non-Stock Option Awards [Member] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Share-Based Awards Stock Compensation Plan [Member] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Net earnings available to common shareholders Weighted-average common shares outstanding (in millions) Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted-average common shares outstanding - basic (in shares) Effect of dilutive securities Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted-average common shares outstanding - diluted (in shares) Antidilutive securities excluded from the calculation of net earnings per share - diluted (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Business Combinations [Abstract] Acquisitions Business Combination Disclosure [Text Block] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] 7S Group GmbH 7S Group GmbH [Member] 7S [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Line Items] Business Acquisition [Line Items] Total cash consideration for acquisitions, net of cash acquired Total cash consideration for acquisitions, net of cash acquired Total cash consideration for acquisitions, net of cash acquired Initial acquisition payments Payments of contingent consideration for acquisitions Payments Of Contingent Considerations For Acquisitions The cash outflow from operating and financing activities for the payments of contingent consideration associated with the acquisitions of businesses. Payment for contingent consideration liability, financing activities Loss contingency, additional consideration sought from the seller of 7S Loss Contingency, Damages Sought, Value Loss Contingency, Estimate of Possible Loss Loss Contingency, Estimate of Possible Loss Payment for contingent consideration liability, operating activities Payment for Contingent Consideration Liability, Operating Activities Schedule of goodwill and intangible assets Schedule of Intangible Assets and Goodwill [Table Text Block] Changes in the carrying value of goodwill by reportable segment and Corporate Schedule of Goodwill [Table Text Block] Schedule of goodwill balances by reporting unit Goodwill Balances By Reporting Unit [Table Text Block] Tabular disclosure of goodwill balances by reporting unit. Other Nonoperating Income (Expense) [Abstract] Schedule of interest and other expenses Schedule of Other Nonoperating Income (Expense) [Table Text Block] Changes in restructuring reserve by reportable segment and Corporate Restructuring and Related Costs [Table Text Block] Dividends [Abstract] Dividends [Abstract] Dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Dividends paid (in dollars per share) Common Stock, Dividends, Per Share, Cash Paid Segment Reporting [Abstract] Segment Data Segment Reporting Disclosure [Text Block] Income Taxes Income Tax Disclosure [Text Block] Schedule of fair value measurements Fair Value, by Balance Sheet Grouping [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior Notes Senior Notes [Member] Notes Due June 2026 - 1.750% Notes Due June 2026 - 1.750% [Member] Notes Due June 2026 - 1.750% [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Principal amount Interest rate Debt Instrument, Interest Rate, Stated Percentage Proceeds from debt Proceeds from Issuance of Debt Debt instrument, discount percentage Debt Instrument, Discount Percentage Debt Instrument, Discount Percentage Effective rate Debt Instrument, Interest Rate, Effective Percentage Statement of Comprehensive Income [Abstract] Other comprehensive (loss) income: Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Net of tax and reclassification adjustments of the change in the balance sheet adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity. Translation adjustments on net investment hedge, net of income taxes of $10.6, $(18.4), $5.8 and $(21.7), respectively Derivatives used in Net Investment Hedge, Net of Tax, Period Increase (Decrease) Translation adjustments of long-term intercompany loans Adjustment for Long-term Intercompany Transactions, Net of Tax Unrealized gain on investments, net of income taxes of $0.1 and $0.6, respectively, for 2017 Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Reclassification of unrealized cumulative gain on investments, net of income taxes of $(3.4), included in retained earnings as of January 1, 2018 upon adoption of new accounting guidance on financial instruments (See Note 12 to the Consolidated Financial Statements) Defined benefit pension plans and retiree health care plan, net of income taxes of $(0.1), $0.2, $0.1 and $0.2, respectively Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Total other comprehensive (loss) income Other Comprehensive Income (Loss), Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Interest and Other Expenses Interest And Other Expenses [Text Block] The entire disclosure for interest income and expense, foreign exchange gains and losses and other miscellaneous non-operating income and expenses. Recently Issued Accounting Standards New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Retirement Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Statement of Financial Position [Abstract] CURRENT ASSETS: Assets, Current [Abstract] Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current OTHER ASSETS: Assets, Noncurrent [Abstract] Accumulated amortization on intangible assets SHAREHOLDERS’ EQUITY: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, issued (in shares) Preferred Stock, Shares Issued Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, authorized (in shares) Common Stock, Shares Authorized Common stock, issued (in shares) Common Stock, Shares, Issued Treasury stock at cost (in shares) Treasury Stock, Shares Jefferson Wells Jefferson Wells [Member] Information pertaining to Jefferson Wells. Goodwill [Roll Forward] Goodwill [Roll Forward] Balance, January 1, 2018 Goodwill acquired Goodwill, Acquired During Period Currency and other impacts Goodwill, Other Increase (Decrease) Balance, June 30, 2018 Net Earnings Per Share Earnings Per Share [Text Block] Interest expense Interest Expense Interest income Interest Income Interest income received from interest bearing assets. The balance includes income earned in return for depositing or lending money that can include income from time deposits, demand deposits, saving accounts, certificates of deposit, money market deposits, bonds, and loans. Foreign exchange (gain) loss Foreign Currency Transaction Gain (Loss), before Tax Miscellaneous (income) expense, net Nonoperating Income (Expense) Interest and other expenses Shareholders' Equity Stockholders' Equity Note Disclosure [Text Block] Schedule of segment reporting information Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information [Table] Schedule of Segment Reporting Information, by Segment [Table] Segment Reconciling Items Segment Reconciling Items [Member] United States Other Americas Other Americas reportable segment [Member] Segment information related to the Americas excluding the United States reportable segment. Other Southern Europe Other Southern Europe reportable segment [Member] Segment information related to the Southern Europe segment excluding France and Italy reportable segments. Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Revenues from services Operating unit profit Operating Unit Profit (loss) Operating unit profit (loss) is equal to segment revenues less cost of services and branch and national headquarters operating costs. This profit measure does not include goodwill and intangible asset impairment charges or amortization of intangibles related to acquisitions, interest and other income and expense amounts or income taxes. Corporate expenses Operating Expenses Intangible asset amortization expense Amortization of Intangible Assets Operating profit Interest and other expenses Franchise fees Franchise Revenue Franchise revenue Total Franchise Revenue Revenues generated by franchise offices. Payment Terms Revenue from Contract with Customer, Payment Term Revenue from Contract with Customer, Payment Term Deferred Revenue Deferred Revenue Revenue recognized related to amounts reported as deferred revenue at prior year end Deferred Revenue, Revenue Recognized Net proceeds from sale of tax credits Proceeds from Sale of Other Receivables Components of accumulated other comprehensive loss, net of tax Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Share-Based Compensation Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Defined Benefit Pension Plans Retiree Health Care Plan Net Periodic Benefit Cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Other Defined Benefit Plan, Other Cost (Credit) Prior service credit Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Total benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Contributions to pension plans Payment for Pension Benefits Contributions to retiree health care plan Payment for Other Postretirement Benefits Estimated employer contribution to pension plans during current fiscal year Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year Non-service component cost Net Periodic Defined Benefits Expense (Reversal Of Expense), Excluding Service Cost Component Net Periodic Defined Benefits Expense (Reversal Of Expense), Excluding Service Cost Component Net earnings attributable to noncontrolling interests Income (Loss) Attributable to Noncontrolling Interest, before Tax ASSETS Cash and cash equivalents Accounts receivable, less allowance for doubtful accounts of $112.5 and $110.8, respectively Accounts Receivable, Net, Current Prepaid Expense and Other Assets, Current Prepaid Expense and Other Assets, Current Total current assets Assets, Current Intangible assets, less accumulated amortization of $353.5 and $339.9, respectively Other assets Other Assets, Noncurrent Total other assets Assets, Noncurrent PROPERTY AND EQUIPMENT: Property, Plant and Equipment, Net [Abstract] Land, buildings, leasehold improvements and equipment Property, Plant and Equipment, Gross Less: accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net property and equipment Property, Plant and Equipment, Net Total assets Assets LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] CURRENT LIABILITIES: Liabilities, Current [Abstract] Accounts payable Accounts Payable And Accrued Temp Payroll Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors and temporary employees for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Employee compensation payable Accrued Salaries Current And Accrued Vacation Current Sum of the carrying values as of the balance sheet date of the obligations incurred through that date and payable for 1) permanent employees' services provided and 2) unused vacation time owed to employees based on the entity's vacation benefit given to its employees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Accrued liabilities Accrued Liabilities, Current Accrued payroll taxes and insurance Accrued Payroll Taxes, Current Value added taxes payable Sales and Excise Tax Payable, Current Short-term borrowings and current maturities of long-term debt Debt, Current Total current liabilities Liabilities, Current OTHER LIABILITIES: Liabilities, Noncurrent [Abstract] Long-term debt Long-term Debt and Capital Lease Obligations Other long-term liabilities Other Liabilities, Noncurrent Total other liabilities Liabilities, Noncurrent ManpowerGroup shareholders' equity Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $.01 par value, authorized 25,000,000 shares, none issued Preferred Stock, Value, Outstanding Common stock, $.01 par value, authorized 125,000,000 shares, issued 116,778,224 and 116,303,729 shares, respectively Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Treasury stock at cost, 51,433,302 and 50,226,525 shares, respectively Treasury Stock, Value Total ManpowerGroup shareholders’ equity Stockholders' Equity Attributable to Parent Noncontrolling interests Stockholders' Equity Attributable to Noncontrolling Interest Total shareholders’ equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and shareholders’ equity Liabilities and Equity Restructuring Costs Restructuring and Related Activities Disclosure [Text Block] Income tax expense (benefit) on translation adjustments on net investment hedge Derivatives used in Net Investment Hedge, Tax Expense (Benefit) Income tax expense (benefit) on unrealized gain on investments Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Income tax expense (benefit) on defined benefit pension plans and retiree health care plan Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Income tax expense (benefit) on reclassification of unrealized cumulative gain on investments Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Equity Method, Tax