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Qualified production activities and research tax credit refund claim - net of reserves Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount Section 199 - Qualified production activities and research tax credit refund claim - net of reserves, percent Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Percent Income Tax Reconciliation Resolution Of Tax Matters Income Tax Reconciliation Resolution Of Tax Matters Income Tax Reconciliation Resolution Of Tax Matters Effective Income Tax Rate Reconciliation Resolution Of Tax Matters Effective Income Tax Rate Reconciliation Resolution Of Tax Matters Effective Income Tax Rate Reconciliation Resolution Of Tax Matters Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Excess tax benefit - Stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Excess tax benefit - Stock-based compensation, percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent Other Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Other, percent Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Provision for income taxes from continuing operations Income Tax Expense (Benefit) Effective Income Tax Rate, Continuing Operations Effective Income Tax Rate Reconciliation, Percent Income Statement [Abstract] Statement [Table] Statement [Table] Restatement [Axis] Restatement [Axis] Restatement [Domain] Restatement [Domain] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Statement [Line Items] Statement [Line Items] REVENUES: Revenues [Abstract] Revenues, Net Revenues, Net Revenues, Net Interest on funds held for clients Interest On Funds Held Clients Interest on assets that, based upon the Company's intent, are restricted for use solely for the purposes of satisfying the obligations to remit funds relating to the Company’s payroll and payroll tax filing services PEO revenues P E O Revenues PEO Revenues TOTAL REVENUES Revenues EXPENSES: Cost of Revenue [Abstract] Operating expenses Operating Costs and Expenses Systems development and programming costs Systems development programming costs Includes all direct/incremental costs of developing, producing, and maintaining the software used in delivering products. Cost, Depreciation and Amortization Cost, Depreciation and Amortization Cost of Goods and Services Sold Cost of Goods and Services Sold Selling, general, and administrative expenses Selling, General and Administrative Expense Interest expense Interest Expense TOTAL EXPENSES Costs and Expenses Other (income)/expense, net Nonoperating Income (Expense) EARNINGS BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Provision for income taxes NET EARNINGS Net Income (Loss) Attributable to Parent Basic earnings per share (in dollars per share) Income (Loss) from Continuing Operations, Per Basic Share BASIC EARNINGS PER SHARE (in dollars per share) Earnings Per Share, Basic Diluted earnings per share (in dollars per share) Income (Loss) from Continuing Operations, Per Diluted Share DILUTED EARNINGS PER SHARE (in dollars per share) Earnings Per Share, Diluted Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Contract with Customer, Asset and Liability [Table Text Block] Contract with Customer, Asset and Liability [Table Text Block] Capitalized Contract Cost [Table Text Block] Capitalized Contract Cost [Table Text Block] Direct pass-through costs, Professional Employer Organization revenues Direct Pass Through Costs P E O Revenues Direct pass-through costs associated with PEO, primarily consisting of payroll wages and payroll taxes. Retirement Benefits [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward] Options outstanding at July 1, 2017 (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Options canceled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Options outstanding at June 30, 2018 (in shares) Options exercisable at June 30, 2018 (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Shares available for future grants, end of year Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Shares reserved for issuance under stock option plans, end of year Shares reserved for issuance under stock option Shares reserved for issuance under stock option Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Price [Roll Forward] Weighted Average Price, beginning of year (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Weighted Average Price, granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Weighted Average Price, exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Weighted Average Price, cancelled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Weighted Average Price, outstanding at June 30, 2016 (in dollars per share) Weighted Average Price, Option exercisable at June 30, 2016 (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Summarized Quarterly Results of Continuing Operations [Abstract] Summarized Quarterly Results of Continuing Operations [Abstract] Quarterly Financial Results (Unaudited) Quarterly Financial Information [Text Block] Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States [Member] UNITED STATES Europe [Member] Europe [Member] CANADA [Member] CANADA Other [Member] Other Geographical Places [Member] Other Geographical Places [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] TOTAL REVENUES Total assets Assets Statement of Comprehensive Income [Abstract] NET EARNINGS Other comprensive income: Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Unrealized net gains/(losses) on available-for-sale securities Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, before Tax Tax effect Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax Reclassification of net losses/(gains) on available-for-sale securities to net earnings Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Tax effect Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Pension net (losses)/gains arising during the year Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Tax effect Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Reclassification of pension liability adjustment to net earnings Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax Tax effect Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax Other comprehensive 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Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Total Pension Assets Excluding Cash [Member] Total Pension Assets Excluding Cash [Member] Total Pension Assets Excluding Cash [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Fair Value of Plan Assets Defined Benefit Plan, Plan Assets, Amount Accounting Policies [Abstract] Basis of Presentation Consolidation, Policy [Policy Text Block] Description of Business Nature of Operations [Text Block] Revenue Recognition Revenue [Policy Text Block] Cash and Cash Equivalents, Policy Cash and Cash Equivalents, Policy [Policy Text Block] Corporate Investments and Funds held for Clients Investment, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy Fair Value Measurement, Policy [Policy Text Block] Property, Plant and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Goodwill and Other Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Foreign Currency Translations Foreign Currency Transactions and Translations Policy [Policy Text Block] Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Earnings Per Share (EPS) Earnings Per Share, Policy [Policy Text Block] Stock-Based Compensation Share-based Payment Arrangement [Policy Text Block] Internal Use Software Internal Use Software, Policy [Policy Text 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12-09, Valuation and Qualifying Accounts Disclosure [Table] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Table] Account Classification [Axis] Account Classification [Axis] Account Classification [Axis] Account Classification [Domain] Account Classification [Domain] [Domain] for Account Classification [Axis] Current [Member] Current [Member] Current [Member] Non-current [Member] Non-current [Member] Non-current [Member] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] SEC Schedule, 12-09, Allowance, Credit Loss [Member] SEC Schedule, 12-09, Allowance, Credit Loss [Member] SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member] SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] Balance at beginning of period SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Charged to costs and expenses SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense Charged to other accounts SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account Deductions SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction Balance at end of period Noncurrent assets Assets for Plan Benefits, Defined Benefit Plan Current liabilities Liability, Defined Benefit Pension Plan, Current Noncurrent liabilities Liability, Defined Benefit Pension Plan, Noncurrent Net amount recognized Defined Benefit Plan, Funded (Unfunded) Status of Plan Goodwill and Intangible Assets Disclosure [Abstract] Goodwill And Intangible Assets, Net Goodwill and Intangible Assets Disclosure [Text Block] Schedule of Finite-Lived Intangible Assets by Major Class [Table] Schedule of Finite-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] Software And Software Licenses [Member] Computer Software, Intangible Asset [Member] Customer Contracts And Lists [Member] Customer Lists [Member] Other Intangible Assets [Member] Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Total - gross Finite-Lived Intangible Assets, Gross Total - accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Other Income, Net [Abstract] Other Income, net Other Expense/(Income), Net Other Income and Other Expense Disclosure [Text Block] Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted average volatility factor Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Weighted average expected life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Weighted average fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line [Axis] Income Statement Location [Axis] Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Report Line [Domain] Income Statement Location [Domain] Operating Expenses [Member] Operating Expenses [Member] Operating expenses [Member] Selling, General and Administrative Expenses [Member] Selling, General and Administrative Expenses [Member] System Development And Programming Costs [Member] System Development And Programming Costs [Member] System development and programming costs [Member] Stock-based compensation expense Share-based Payment Arrangement, Expense Income Tax Benefit Share-based Payment Arrangement, Exercise of Option, Tax Benefit Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Segment Reporting Information, by Segment [Axis] Segments [Axis] Reporting Segment [Domain] Segments [Domain] Employer Services [Member] Employer Services Segment [Member] Employer Services Segment. PEO Services [Member] Professional Employee Organization Services Segment [Member] Professional Employee Organization Services Segment [Member] Other [Member] Other Segments [Member] EARNINGS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES Capital Expenditures from continuing operations Capital Expenditures from Continuing Operations Capital Expenditures from Continuing Operations Depreciation, Depletion and Amortization Depreciation, Depletion and Amortization Number of Reportable Segments Number of Reportable Segments Short-Term Financing [Abstract] Short-term Financing Short-Term Financing Short-term Debt [Text Block] Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] CHSA and COBRA [Member] CHSA and COBRA [Member] CHSA and COBRA [Member] 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] Disposal Date Disposal Date Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Debt Disclosure [Abstract] Schedule of Debt [Table Text Block] Schedule of Debt [Table Text Block] Financial Data By Segment Segment Reporting Disclosure [Text Block] Income Tax Examination [Table] Income Tax Examination [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Foreign Tax Authority [Member] Foreign Tax Authority [Member] Domestic Tax Authority [Member] Domestic Tax Authority [Member] Internal Revenue Service (IRS) [Member] Internal Revenue Service (IRS) [Member] State and Local Jurisdiction [Member] State and Local Jurisdiction [Member] Income Taxes Payable [Member] Income Taxes Payable [Member] Income Taxes Payable Income Tax Items [Line Items] Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Tax Cuts and Jobs Act, Incomplete Accounting, Undistributed Accumulated Earnings of Foreign Subsidiary, Provisional Unrecognized Deferred Tax Liability Tax Cuts and Jobs Act, Incomplete Accounting, Undistributed Accumulated Earnings of Foreign Subsidiary, Provisional Unrecognized Deferred Tax Liability Accrual On Foreign Withholding Taxes Accrual On Foreign Withholding Taxes Accrual On Foreign Withholding Taxes Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Tax Cuts and Jobs 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Carryforwards, Expiration Date Operating Loss Carryforwards, Expiration Date Operating loss carry forwards not subject to expiration Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration Operating Loss Carryforwards Operating Loss Carryforwards Valuation Allowance Deferred Tax Assets, Valuation Allowance Income Taxes Paid Income Taxes Paid Unrecognized Tax Benefits Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits, Interest on Income Taxes Expense Unrecognized Tax Benefits, Interest on Income Taxes Expense Unrecognized Tax Benefits, Interest on Income Taxes Accrued Unrecognized Tax Benefits, Interest on Income Taxes Accrued Unrecognized Tax Benefits, Income Tax Penalties Accrued Unrecognized Tax Benefits, Income Tax Penalties Accrued Tax Settlements Future Impact Potential On Earnings Maximum Tax Settlements Future Impact Potential On Earnings Maximum Tax Settlements Future Impact Potential On Earnings Maximum Max Expected Cash Payment On Tax Settlements Max Expected Cash Payment On Tax Settlements Max Expected Cash Payment on tax settlements related to various jurisdictions and tax periods in the next twelve months Tax Cuts and Jobs Act, Accounting Complete [true false] Tax Cuts and Jobs Act, Accounting Complete [true false] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Property, Plant and Equipment [Abstract] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Investment Secondary Categorization [Axis] Investment Secondary Categorization [Axis] Investments by Secondary Categorization [Domain] Investments by Secondary Categorization [Domain] Corporate Investments [Member] Corporate Investments [Member] Corporate investments [Member] Funds Held For Clients [Member] Funds Held For Clients [Member] Funds held for clients [Member] Money market securities and other cash equivalents - Amortized Cost Cash Equivalents At Amortized Cost Money market securities and other cash equivalents - amortized cost Cash Equivalents At Gross Unrealized Gains Cash Equivalents At Gross Unrealized Gains Money market securities and other cash equivalents - Unrealized Gains Cash Equivalents At Gross Unrealized Losses Cash Equivalents At Gross Unrealized Losses Money market securities and other cash equivalents - Gross Unrealized Losses Money market securities and other cash equivalents - Fair Value Cash Equivalents, at Carrying Value Total available-for-sale securities - Amortized Cost Available-for-sale Securities, Amortized Cost Basis Available for Sale Securities - Unrealized Gains Available for Sale Securities - Unrealized Gains Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as availble-for-sale securities Available for sale securities - Unrealized Loss Available for sale securities - Unrealized Loss Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities Total available-for-sale securities - Fair Value Available-for-sale Securities Total corporate investments and funds held for clients - Amortized Cost Total Corporate Investments And Funds Held For Clients Amortized Cost Total corporate investments and funds held for clients - amortized cost Total corporate investments and funds held for clients - Gross Unrealized Gains Total Corporate Investments And Funds Held For Clients Gross Unrealized Gains Total corporate investments and funds held for clients - gross unrealized gains Total corporate investments and funds held for clients - Gross Unrealized Losses Total Corporate Investments And Funds Held For Clients Gross Unrealized Losses Total corporate investments and funds held for clients - gross unrealized losses Total corporate investments and funds held for clients - Fair Value Total Corporate Investments And Funds Held For Clients Fair Value Total corporate investments and funds held for clients - fair value Twelve months ending June 30, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two Twelve months ending June 30, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three Twelve months ending June 30, 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four Twelve months ending June 30, 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Finite-Lived Intangible Assets, Amortization Expense, after Year Five Finite-Lived Intangible Assets, Amortization Expense, after Year Five Schedule of Quarterly Financial Information Quarterly Financial Information [Table Text Block] Property, Plant and Equipment Property, Plant and Equipment Disclosure [Text Block] Projected benefit obligation Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Accumulated benefit obligation Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation Fair value of plan assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets Marketable Securities [Table] Marketable Securities [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Marketable Securities [Line Items] Marketable Securities [Line Items] Restricted cash and cash equivalents held to satisfy client funds obligations Restricted Cash and Cash Equivalents Available-for-sale Securities, Restricted Available-for-sale Securities, Restricted Total funds held for clients Funds Held Clients Represents assets that, based upon the Company's intent, are restricted for use solely for the purposes of satisfying the obligations to remit funds relating to the Company’s payroll and payroll tax filing services Components Of Stock-Based Compensation Expense Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Changes In Stock Options Outstanding Share-based Payment Arrangement, Option, Activity [Table Text Block] Time Based Restricted Shares and Units Time Based Restricted Shares and Units [Table Text Block] [Table Text Block] Disclosure of the number for Time-Based restricted stock and Time-Based restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. Performance Based Restricted shares and units Performance Based Restricted shares and units [Table Text Block] Disclosure of the number for Performance-Based restricted stock and Performance based restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. Assumptions Used To Estimate Fair Value For Stock Options Granted Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Weighted average fair value of restricted stock granted Weighted average fair value of restricted stock granted [Table Text Block] Weighted average fair value of restricted stock granted [Text Block] Schedule of Net Funded Status Schedule of Net Funded Status [Table Text Block] Schedule of Amounts Recognized in Balance Sheet Schedule of Amounts Recognized in Balance Sheet [Table Text Block] Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block] Components Of Net Pension Expense Schedule of Net Benefit Costs [Table Text Block] Schedule of Assumptions Used Defined Benefit Plan, Assumptions [Table Text Block] Defined Benefit Plan Assumptions Used Calculating Net Pension Expense Defined Benefit Plan Assumptions Used Calculating Net Pension Expense [Table Text Block] Defined Benefit Plan Assumptions Used Calculating Net Pension Expense [Text Block] Schedule of Allocation of Plan Assets Schedule of Allocation of Plan Assets [Table Text Block] Defined Benefit Plan Target Allocation Percentage Defined Benefit Plan Target Allocation Percentage [Table Text Block] Defined Benefit Plan Target Allocation Percentage [Text Block] Fair Value, Measurement Inputs, Disclosure Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] PEO Services [Member] Peo Services Segment [Member] PEO Services Segment. Other Segments [Member] Goodwill Goodwill [Line Items] Goodwill [Roll Forward] Goodwill [Roll Forward] Beginning balance Goodwill Additions and other adjustments Goodwill, Period Increase (Decrease) Currency translation adjustments Goodwill, Foreign Currency Translation Gain (Loss) Ending balance Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Award Type and Plan Name [Axis] Award Type [Axis] Share-based Compensation Arrangements by Share-based Payment Award, Award Type and Plan Name [Domain] Award Type [Domain] Performance Based Restricted Stock and Units [Domain] Performance Based Restricted Stock and Units [Domain] Performance Based Restricted Stock and Units [Domain] Performance-Based Restricted Stock [Member] Performance Based Restricted Stock [Member] Performance-based restricted stock [Member] Performance Based Restricted Stock Unit [Domain] Performance Based Restricted Stock Unit [Domain] Performance Based Restricted Stock Unit [Domain] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Restricted shares/units outstanding at July 1, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Restricted shares/units granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted shares/units vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Restricted shares/units forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Restricted shares/units outstanding at June 30, 2016 Business Combinations [Abstract] Acquisitions Business Combination Disclosure [Text Block] Due in one year or less Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Due after one year to two years Available For Sale Securities Debt Maturities Due After One Year Up To Two Fair Value This item represents the fair value of debt securities which are expected to mature after one year up to two years after the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. Due after two years to three years Available For Sale Securities Debt Maturities Due After Two Year Up To Three Fair Value This item represents the fair value of debt securities which are expected to mature after two years up to three years of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. Due after three years to four years Available For Sale Securities Debt Maturities Due After Three Year Up To Four Fair Value This item represents the fair value of debt securities which are expected to mature after three years up to four years of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. Due after four years Available For Sale Securities Debt Maturities Due After Four Fair Value This item represents the fair value of debt securities which are expected to mature after four years of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. Total available-for-sale securities Debt Securities, Available-for-sale Cover page. Document Type Document Type Entity Public Float Entity Public Float Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Amendment Flag Amendment Flag Document Period End Date Document Period End Date Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Schedule of Valuation and Qualifying Accounts Disclosure SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] Income Tax From Continuing Operations Provision For Income Tax Components Disclosure Income Tax From Continuing Operations Provision For Income Tax Components Disclosure [Text Block] Earnings from Continuing Operations by Geographic Location Schedule Of Components Of Provision (Benefit) For Income Taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Reconciliation Between Federal Statutory Tax And Effective Tax Rate Reconciliation Between Federal Statutory Tax And Effective Tax Rate [Text Block] Reconciliation Between Federal Statutory Tax And Effective Tax Rate [Text Block] Components Of Deferred Tax Assets And Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Summary of Income Tax Contingencies Summary of Income Tax Contingencies [Table Text Block] Summary of Income Tax Examinations Summary of Income Tax Examinations [Table Text Block] Schedule of Short-term Debt [Table] Schedule of Short-term Debt [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 364-Day Credit Agreement [Member] Three Hundred And Sixty Four Day Credit Facility [Member] Three hundred and sixty four day credit facility [Member] Credit Facility Expiring In June Two Thousand Twenty Four [Member] Credit Facility Expiring In June Two Thousand Twenty Four [Member] Credit Facility Expiring In June Two Thousand Twenty Four [Member] Short-Term Commercial Paper Program [Member] Short Term Commercial Paper Program [Member] Short-term commercial paper program Reverse Repurchase Agreements [Member] Reverse Repurchase Agreements [Member] Reverse Repurchase Agreements [Member] Credit Facility Expiring In June Two Thousand Twenty One [Member] Credit Facility Expiring In June Two Thousand Twenty Three [Member] Credit Facility Expiring In June Two Thousand Twenty Three [Member] Commercial Paper [Member] Commercial Paper [Member] Short-term Debt [Line Items] Short-term Debt [Line Items] Maximum borrowing capacity under credit facilities Line of Credit Facility, Maximum Borrowing Capacity Term of credit Line Of Credit Facility Term Of Credit Line Of Credit Facility Term Of Credit Expiration date of credit facilities Line of Credit Facility, Expiration Date Debt Instrument, Extension Option Term Debt Instrument, Extension Option Term Debt Instrument, Extension Option Term Line of credit facility potentially available increase in maximum borrowing capacity Line of credit facility potentially available increase in maximum borrowing capacity Line of credit facility potentially available increase in maximum borrowing capacity. Credit borrowings Short-term Debt Aggregate amount of commercial paper issuable under the short-term commercial paper program Short-term Debt, Maximum Borrowing Capacity Short-term Debt, Maximum Borrowing Capacity Maturities of commercial paper range Maturities Of Commercial Paper Range Maturities of commercial paper range. Commercial Paper Commercial Paper Weighted average maturity of borrowings under the short-term commercial paper program Commercial Paper Weight Average Maturity Reflects the calculated weighted average maturity of the Company's commercial paper Maturities of short-term funding agreements Maturities Of Short Term Funding Agreements Maturities Of Short-Term Funding Agreements Obligations under reverse repurchase agreements Obligations under reverse repurchase agreements Obligations under reverse repurchase agreements Short-term Debt, Average Outstanding Amount Short-term Debt, Average Outstanding Amount Debt Instrument, Interest Rate During Period Debt Instrument, Interest Rate During Period Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Fair Value of Plan Assets, beginning of year Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Currency translation adjustments Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss) Benefits Paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Fair Value of Plan Assets, end of year Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Benefit obligation at beginning of year Defined Benefit Plan, Benefit Obligation Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Actuarial (gains)/losses Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Currency translation adjustments Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Curtailments and special termination benefits Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement and Curtailment Benefits Paid Projected benefit obligation at end of year Funded status - plan assets less benefit obligations Restatement Adjustment [Member] Restatement Adjustment [Member] Reclassification out of Accumulated Other Comprehensive Income [Abstract] Reclassification out of Accumulated Other Comprehensive Income [Abstract] Reclassification out of Accumulated Other Comprehensive Income Disclosure of Reclassification Amount [Text Block] Statement of Financial Position [Abstract] Long-term Marketable Securities Under Reverse Repurchase Agreements Long-term Marketable Securities Under Reverse Repurchase Agreements Long-term Marketable Securities Under Reverse Repurchase Agreements Assets [Abstract] Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts receivable, net of allowance for doubtful accounts of $54.9 and $51.3, respectively Accounts Receivable, after Allowance for Credit Loss, Current Other current assets Other Assets, Current Total current assets before funds held for clients Total Assets Before Funds Held Clients Total assets before funds held for clients Funds held for clients Total current assets Assets, Current Long-term receivables, net of allowance for doubtful accounts of $0.4 and $0.5, respectively Accounts Receivable, after Allowance for Credit Loss, Noncurrent Property, plant and equipment, net Property, Plant and Equipment, Net Capitalized Contract Cost, Net Capitalized Contract Cost, Net Other assets Other Assets, Noncurrent Goodwill Intangible assets, net Total assets Liabilities And Stockholders Equity Abstract Liabilities and Equity [Abstract] Liabilities Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued expenses and other current liabilities Accrued Liabilities, Current Accrued payroll and payroll-related expenses Employee-related Liabilities, Current Dividends payable Dividends Payable Short-term deferred revenues Deferred Revenue and Credits, Current Income taxes payable Accrued Income Taxes, Current Total current liabilities before client funds obligations Total current liabilities before client funds obligations Total current liabilities before client funds obligations Client funds obligations Client funds obligations Represent the Company's contractual obligations to remit funds to satisfy clients' payroll and tax payment obligations and are recorded on the Balance Sheet at the time that the Company impounds funds from clients. Total current liabilities Liabilities, Current Long-term debt Long-term Debt, Excluding Current Maturities Other liabilities Other Liabilities, Noncurrent Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Long-term deferred revenues Deferred Revenue, Noncurrent Total liabilities Liabilities Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $1.00 par value: Authorized, 0.3 shares; issued, none Preferred Stock, Value, Issued Common stock, $0.10 par value: authorized, 1,000.0 shares; issued, 638.7 shares at June 30, 2019 and June 30, 2018; outstanding, 434.2 and 438.8 shares at June 30, 2019 and June 30, 2018, respectively Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Treasury stock - at cost: 204.5 and 199.9 shares at June 30, 2019 and June 30, 2018, respectively Treasury Stock, Value Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Cash And Cash Equivalents Under Reverse Repurchase Agreements Cash And Cash Equivalents Under Reverse Repurchase Agreements Cash And Cash Equivalents Under Reverse Repurchase Agreements Obligations under reverse repurchase agreements (A) Type Of Non-Service Component [Axis] Type Of Non-Service Component [Axis] Type Of Non-Service Component [Axis] Type Of Non-Service Component [Domain] Type Of Non-Service Component [Domain] [Domain] for Type Of Non-Service Component [Axis] Non-Cash Settlement [Member] Non-Cash Settlement [Member] Non-Cash Settlement [Member] Special Termination Benefits [Member] Special Termination Benefits [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Cash and Cash Equivalents [Member] Cash and Cash Equivalents [Member] Time Based Restriced Stock granted during or after Fiscal 2019 [Domain] Time Based Restriced Stock granted during or after Fiscal 2019 [Domain] Time Based Restricted Stock granted during or after Fiscal 2019 [Domain] Time Based Restricted Stock granted during Fiscal 2013 [Domain] [Domain] Time Based Restricted Stock granted during Fiscal 2013 [Domain] Time Based Restricted Stock and Units granted during Fiscal 2013 [Domain] Employee Stock [Member] Employee Stock [Member] Non-Vested Stock Options [Member] Nonvested Stock Options [Member] Nonvested Stock Options [Member] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Non-Vested Restricted Stock [Member] Nonvested Restricted Stock [Member] Nonvested Restricted Stock [Member] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Stock options - term for stock options granted, in years Share Based Compensation Arrangement By Share Based Payment Award Options Granted Contractual Term 1 Share Based Compensation Arrangement By Share Based Payment Award Options Granted Contractual Term 1 Vesting term options granted Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Share Based Compensation Arrangement By Share Based Payment Award Performance Period Share Based Compensation Arrangement By Share Based Payment Award Performance Period Share Based Compensation Arrangement By Share Based Payment Award Performance Period Minimum percentage that will ultimately vest under performance-based restricted stock awards based on performance target Minimum percentage that will ultimately vest under performance-based restricted stock awards based on performance target Minimum percentage that will ultimately vest under performance-based restricted stock awards based on performance target. Maximum percentage that will ultimately vest under performance-based restricted stock awards based on performance target Maximum percentage that will ultimately vest under performance-based restricted stock awards based on performance target Maximum percentage that will ultimately vest under performance-based restricted stock awards based on performance target Purchase price of common stock as percentage of market value Percentage of Market Value paid for Company Stock Percentage of Market Value paid for Company Stock Stock repurchased during period (in shares) Stock Repurchased During Period in Treasury, Shares Stock Repurchased During Period in Treasury, Shares Cash payments for Restricted Stock Units Employee Benefits and Share-based Compensation Total remaining unrecognized compensation cost Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Weighted-average remaining requisite vesting period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Aggregate intrinsic value of stock options outstanding and exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Weighted average remaining life of stock options outstanding and exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate intrinsic value for options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Award requisite service period Service Duration for Pension Plans Employees are fully vested upon completion of three years of service VERP Minimum Age Requirement Voluntary Early Retirement Program Minimum Age Requirement Voluntary Early Retirement Program Minimum Age Requirement VERP Minimum Period Voluntary Early Retirement Program, Minimum Period Voluntary Early Retirement Program, Minimum Period of Service Required VERP Number of Eligible Associates Voluntary Early Retirement Program Number of Eligible Associates Voluntary Early Retirement Program Number of Eligible Associates VERP Percent of Eligible Associates from Total Voluntary Early Retirement Program, Percent of Eligible Associates from Total Voluntary Early Retirement Program, Percent of Eligible Associates from Total Associates Opting to Participate in VERP Associates Opting to Participate in VERP Associates Opting to Participate in VERP VERP Expenses VERP Expenses Very Early Retirement Program Expenses VERP Period of Health Care Coverage Following Retirement VERP, Period of Health Care Coverage Following Retirement VERP, Period of Health Care Coverage Following Retirement VERP Expenses in SG&A VERP, charge recorded under SG&A VERP, charge recorded under SG&A Supplemental Officers Retirement Plan Freeze Date Supplemental Officers Retirement Plan Freeze Date Supplemental Officers Retirement Plan Freeze Date Defined Benefit Plan, Accumulated Benefit Obligation Defined Benefit Plan, Accumulated Benefit Obligation Defined Benefit Plan, Accumulated Other Comprehensive Income Net Gains (Losses), after Tax Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Defined Benefit Plan, Accumulated Other Comprehensive Income Net Prior Service Cost (Credit), after Tax Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Defined Benefit Plan, Plan Assets, Contributions by Employer Expected future plan benefit payment - 2019 Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months Expected future plan benefit payment - 2020 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Expected future plan benefit payment - 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year Three Expected future plan benefit payment - 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Expected future plan benefit payment - 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Five Expected future plan benefit payment - 2024 to 2028 Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment Additional estimated future contribution Additional estimated future contribution next fiscal year The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year, excluding the next fiscal year contributions to date. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Highly Compensated Employee Contribution Percentage To Retirement And Saving Plan Highly Compensated Employee Contribution Percentage To Retirement And Saving Plan Highly Compensated Employee Contribution Percentage To Retirement And Saving Plan Defined Contribution Plan, Cost Defined Contribution Plan, Cost Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] United States Fixed Income Securities Debt Security, Corporate, US [Member] United States Equity Securities [Member] United States Equity Securities [Member] United States Equity Securities [Member] International Securities [Member] International Securities [Member] International Securities [Member] Global Equity Securities [Domain] Global Equity Securities [Domain] Global Equity Securities [Domain] Pension plans' asset allocations Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage Divestiture Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Restructuring and Related Activities [Abstract] Service Alignment Initiative Restructuring and Related Activities Disclosure [Text Block] Revenues Gross profit Gross Profit Earnings before income taxes Net earnings Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Investment [Line Items] Investment [Line Items] Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land and Building [Member] Land and Building [Member] Data Processing Equipment [Member] Data Processing Equipment [Member] Data Processing Equipment [Member] Furniture and Fixtures [Member] Furniture and Fixtures [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Depreciation Expense Depreciation, Nonproduction Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross Accumulated Depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, Plant and Equipment, Net Time-Based Restricted Stock [Member] Time Based Restricted Stock [Member] Time-Based Restricted Stock [Member] Time-Based Restricted Stock Units [Member] Time-Based Restricted Stock Units [Member] Time-Based Restricted Stock Units [Member] Changes In Goodwill Schedule of Goodwill [Table Text Block] Components Of Finite-Lived Intangible Assets Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block] Schedule Of Finite-Lived Intangible Assets, Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Service cost - benefits earned during the period Interest cost on projected benefits Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Net amortization and deferral Defined Benefit Plan, Amortization of Gain (Loss) Net pension expense Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Employee Benefit Plans Compensation and Employee Benefit Plans [Text Block] Commitments and Contingencies Disclosure [Abstract] Purchase commitments relating to June 30, 2018 Unrecorded Unconditional Purchase Obligation Purchase commitments relating to June 30, 2019 Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months Purchase commitments relating to June 30, 2020 Unrecorded Unconditional Purchase Obligation, Due within Two Years Other expense/(income), net Schedule of Other Nonoperating Income (Expense) [Table Text Block] Federal Home Loan Banks [Member] Federal Home Loan Bank Certificates and Obligations (FHLB) [Member] Federal Farm Credit Banks [Member] Federal Farm Credit Banks [Member] Federal Farm Credit Banks [Member] Commercial Mortgage Backed Securities [Member] Commercial Mortgage Backed Securities [Member] Debt Security, Corporate, Non-US [Member] Debt Security, Corporate, Non-US [Member] Supranational Bonds [Member] Supranational Bonds [Member] Supranational Bonds [Member] Fixed Rate Credit Card [Member] Fixed Rate Credit Card [Member] Fixed Rate Credit Card [Member] Asset-Backed Auto Loan Receivables [Member] Asset Backed Auto Loan Receivables [Member] Securities collateralized by physical property Asset-Backed Equipment Lease Receivable [Member] Asset-Backed Equipment Lease Receivable [Member] Asset-Backed Equipment Lease Receivable [Member] Rate Reduction Receivable [Member] Rate Reduction Receivable [Member] Rate Reduction [Member] Sovereign Bonds [Member] Sovereign Bonds [Member] Sovereign Bonds [Member] Available-for-sale securities - fair value Earliest corporate bond maturity date Earliest Corporate bond debt maturity date Earliest Corporate bond debt maturity date Latest corporate bond maturity date Latest corporate debt maturity date Latest corporate debt maturity date Earliest non-callable debt maturity date Earliest U.S. Treasury maturity date Earliest U.S. Treasury maturity date Latest non-callable debt maturity date Latest U.S Treasury maturity date Latest U.S Treasury maturity date Client Fund Obligation repayment period Client Fund Obligation repayment period Period of time from the Balance Sheet Date that client fund obligations has to be repaid Funds held for Clients Held-in Grantor Trust Client Funds Held in Grantor Trust Client Funds Held in Grantor Trust Client funds investments with original maturities Client Funds Investments Original Maturity Period Client funds investments, maturity period. Percentage of the available-for-sale securities were rated AAA or AA Percentage Of The Available-For-Sale Securities Were Rated AAA Or AA Percentage of the available-for-sale securities were rated AAA or AA Award Type [Axis] Award Type [Domain] Commitments And Contingencies Commitments and Contingencies Disclosure [Text Block] United States Income (Loss) from Continuing Operations before Income Taxes, Domestic Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Retained Earnings [Member] Treasury Stock [Member] Treasury Stock [Member] AOCI Attributable to Parent [Member] AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss), Net of Tax Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares issued, beginning of period Common Stock, Shares, Issued Stockholders' Equity, balance, beginning of period Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Other comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Stock-based compensation expense Stock Based Compensation Expense in Equity Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Issuances relating to stock compensation plans Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Treasury stock Treasury Stock, Value, Acquired, Cost Method Dividends, Stock Dividends, Stock Common stock, shares issued, end of period Stockholders' Equity, balance, end of period Other Stockholders' Equity Note, Spinoff Transaction Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Accumulated Translation Adjustment [Member] Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Net Unrealized Investment Gain (Loss) [Member] AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Accumulated Defined Benefit Plans Adjustment [Member] Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Accumulated Other Comprehensive, beginning balance Other comprehensive income/(loss) before reclassification adjustments Other Comprehensive Income (Loss), before Reclassifications, before Tax Tax effect Other Comprehensive Income (Loss) before Reclassifications, Tax Reclassification adjustments to net earnings Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Tax effect Reclassification From Accumulated Other Comprehensive Income, Current Period, Tax Reclassification From Accumulated Other Comprehensive Income, Current Period, Tax Accumulated Other Comprehensive, ending balance Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Revenue Recognition Restatement [Abstract] Revenue Recognition Restatement [Abstract] Schedule of Revenue Recognition Restatement Schedule of Error Corrections and Prior Period Adjustment Restatement [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2014-09 [Member] Accounting Standards Update 2014-09 [Member] ASU 2017-07 [Member] ASU 2017-07 [Member] ASU 2017-07 [Member] Previously Reported [Member] Previously Reported [Member] Revenue Recognition Restatement Error Corrections and Prior Period Adjustments Restatement [Line Items] Other Assets, Current Revenue, Service Agreements, Term Revenue, Service Agreements, Term Revenue, Service Agreements, Term PEO revenues Operating expenses Selling, general, and administrative expenses Interest Expense Total Expenses Other expense/(income), net Provision for income taxes Assets, Current Other Assets, Noncurrent Deferred Revenue and Credits, Current Liabilities, Current Deferred Tax Liabilities, Net, Noncurrent Deferred Revenue, Noncurrent Liabilities Retained Earnings (Accumulated Deficit) Stockholders' Equity Attributable to Parent Liabilities and Equity Capitalized Contract Cost, Amortization Capitalized Contract Cost, Amortization Deferred Income Tax Expense (Benefit), Net of Disposals Deferred Income Tax Expense (Benefit), Net of Disposals Deferred Income Tax Expense (Benefit), Net of Disposals Increase (Decrease) in Other Operating Assets Increase (Decrease) in Other Operating Assets Increase (Decrease) in Accrued Liabilities Increase (Decrease) in Accrued Liabilities Net Cash Provided by (Used in) Operating Activities Net Cash Provided by (Used in) Operating Activities Discount Rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Increase in compensation levels Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Marketable Securities, Current Marketable Securities, Current Long-term marketable securities Marketable Securities, Noncurrent Total corporate investments Investments SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Accrued expenses not currently deductible Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals Stock-based compensation expense Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Foreign Tax Credits Deferred Tax Assets, Tax Credit Carryforwards, Foreign Net operating losses Deferred Tax Assets, Unrealized Losses on Trading Securities Deferred Tax Assets, Unrealized Losses on Trading Securities Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Other Deferred Tax Assets, Other Deferred Tax Assets, Gross Deferred Tax Assets, Gross Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Prepaid retirement benefits Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Deferred Revenue Deferred Tax Liabilities, Tax Deferred Income Fixed and intangible assets Deferred Tax Liabilities Fixed And Intangible Assets Deferred Tax Liabilities Fixed And Intangible Assets Prepaid expenses Deferred Tax Liabilities, Prepaid Expenses Unrealized investment gains, net Deferred Tax Liabilities, Unrealized Gains on Trading Securities Tax on unrepatriated earnings Deferred Tax Liabilities, Undistributed Foreign Earnings Other Deferred Tax Liabilities, Other Deferred Tax Liabilities Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net Deferred Tax Assets, Net 2018 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2019 Operating Leases, Future Minimum Payments, Due in Two Years 2020 Operating Leases, Future Minimum Payments, Due in Three Years 2021 Operating Leases, Future Minimum Payments, Due in Four Years 2022 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Corporate Investments And Funds Held For Clients Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Income Taxes Income Tax Disclosure [Text Block] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Restructuring and Related Costs Restructuring and Related Costs [Table Text Block] Estimated Useful Lives Estimated Useful lives [Table Text Block] [Table Text Block] for Estimated Useful lives for Property, Plant, and Equipment [Table] Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Notes due on 2020 [Member] Notes due on 2020 [Member] Notes due on 2020 [Member] Notes due on 2025 [Member] Notes due on 2025 [Member] Notes due on 2025 [Member] Other Debt Obligations [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Maturity Date Debt Instrument, Maturity Date Notes Payable Notes Payable Debt Instrument, Interest Rate, Effective Percentage Debt Instrument, Interest Rate, Effective Percentage Debt Instrument, Face Amount Debt Instrument, Face Amount Long-term Debt, Fair Value Long-term Debt, Fair Value Debt Instrument, Term Debt Instrument, Term Debt, Current Debt, Current Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums Other Other Long-term Debt, Noncurrent Available-for-sale Securities Available-for-sale Securities [Table Text Block] Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block] Classification Of Corporate Investments On The Consolidated Balance Sheets Schedule Of Corporate Investments Text Block This element represents the carrying amounts of all corporate investments on the Consolidated Balance Sheets including cash and cash equivalents, short-term and long-term investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. This element excludes same type of investments held as funds held for clients which is disclosed in a separate table. Schedule Of Investment Of Funds Held For Clients Schedule Of Investment Of Funds Held For Clients Text Block This element represents the carrying amounts of all investments of funds held for clients on the Consolidated Balance Sheets including cash and cash equivalents, short-term and long-term investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. Expected Maturities Of Available-For-Sale Securities Schedule Of Expected Maturities Of Available For Sale Securities Text Block This element represents the expected maturities broken out by maturity date of all investments categorized as available-for-sale Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Employee separation benefits [Member] Employee Severance [Member] Other initiative costs [Member] Other Restructuring [Member] Gain on Sale of Building [Member] Gain on Sale of Building [Member] Gain on Sale of Building [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Restructuring Charges, Net of Reversals Restructuring Charges, Net of Reversals Restructuring Charges, Net of Reversals Cumulative amount from inception Restructuring and Related Cost, Incurred Cost Beginning balance Restructuring Reserve Charged to expense Restructuring Charges Reversals Restructuring Reserve, Accrual Adjustment Cash payments Payments for Restructuring Non-cash utilization Restructuring Reserve, Settled without Cash Ending balance Accounting Standards Update 2016-02 [Member] Accounting Standards Update 2016-02 [Member] Building [Member] Building [Member] Scenario [Axis] Scenario [Axis] Scenario [Domain] Scenario [Domain] Forecast [Member] Forecast [Member] Summary of Significant Accounting Policies [Line Items] Property, Plant and Equipment and intangibles [Line Items] Property, Plant and Equipment and intangibles [Line Items] Stockholders' Equity Note, Spinoff Transaction Net Income (Loss) Attributable to Parent Operating Leases, Rent Expense Operating Leases, Rent Expense Percent of Level Two Investment Pricing Inputs Provided by Independent Pricing Service Percent of Level Two Investment Pricing Inputs Provided by Pricing Service Percent of Level Two Investment Pricing Inputs Provided by Pricing Service Property, Plant, and Equipment Useful Life Property, Plant and Equipment, Useful Life Effect of Employee Stock Option Shares Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Effect of Employee Restricted Stock Shares Effect of Employee Restricted stock Shares On Weighted Average Number of Diluted Shares Outstanding Effect of Employee Restricted stock Shares On Weighted Average Number of Diluted Shares Outstanding EPS from continuing operations, Basic (in dollars per share) EPS from continuing operations, Diluted (in dollars per share) Options excluded from the calculation of diluted earnings per share because their exercise prices exceeded the average market price (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Threshold of coverage for all losses per occurrence covered by reinsurance arrangement, next fiscal year Threshold of coverage for all losses per occurrence covered by reinsurance arrangement, next fiscal year Threshold of coverage for all losses per occurrence covered by reinsurance arrangement, next fiscal year Concentration Risk, Credit Risk, Financial Instruments, Off-balance Sheet Risk Letters of credit, Off-balance Sheet Risk Letters of credit with off-balance sheet credit risk (standby letters of credit). These letters of credit mitigate the risk if the Company were to fail to reimburse the third party for worker's compensation claims. Payments for Reinsurance Payments for Reinsurance Internal Use Software Life of Asset Internal Use Software Life of Asset Useful life of major software purchases and software developed or obtained for internal use Letters of Credit Outstanding, Amount Letters of Credit Outstanding, Amount Operating Lease, Right-of-Use Asset Operating Lease, Right-of-Use Asset Operating Lease, Liability Operating Lease, Liability Revenue, Capitalized Costs Fulfillment Period, Description of Timing Revenue, Capitalized Costs Fulfillment Period, Description of Timing Revenue, Capitalized Costs Fulfillment Period, Description of Timing Allowance for doubtful accounts, current Accounts Receivable, Allowance for Credit Loss, Current Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common stock, shares outstanding Common Stock, Shares, Outstanding Treasury stock, shares Treasury Stock, Shares Allowance for doubtful accounts, long-term Accounts Receivable, Allowance for Credit Loss, Noncurrent Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Capitalized Contract Cost [Axis] Capitalized Contract Cost [Axis] Capitalized Contract Cost [Domain] Capitalized Contract Cost [Domain] Deferred costs to obtain a contract [Member] Deferred costs to obtain a contract [Member] Deferred costs to obtain a contract [Member] Deferred costs to fulfill a contract [Member] Deferred costs to fulfill a contract [Member] Deferred costs to fulfill a contract [Member] Segments [Axis] Employer Services Segment [Member] Professional Employee Organization Services Segment [Member] HCM [Member] HCM [Member] HCM [Member] HRO [Member] HRO [Member] HRO [Member] PEO [Member] PEO [Member] PEO [Member] Global [Member] Global [Member] Global [Member] client fund interest [Member] client fund interest [Member] client fund interest [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Contract with Customer, Liability Contract with Customer, Liability Revenue from Contract with Customer, Excluding Assessed Tax Revenue from Contract with Customer, Excluding Assessed Tax Contract with Customer, Liability, Revenue Recognized Contract with Customer, Liability, Revenue Recognized Contract With Customer, Liability, Deferral Net Of Revenue Recognized And Foreign Currency Translation Contract With Customer, Liability, Deferral Net Of Revenue Recognized And Foreign Currency Translation Amount of revenue deferred as an obligation to transfer good or service to customer for which consideration from customer has been received or is due, net of the amount of revenue recognized in the period from deferrals during the period. Contract With Customer, Liability, Increase (Decrease) From Foreign Currency Translation Contract With Customer, Liability, Increase (Decrease) From Foreign Currency Translation Contract With Customer, Liability, Increase (Decrease) From Foreign Currency Translation Debt Disclosure [Text Block] Debt Disclosure [Text Block] Schedule of Business Combination Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Other Components [Member] Other Components [Member] Other Components [Member] Impairment of Intangible Assets, Finite-lived Impairment of Intangible Assets, Finite-lived Interest income on corporate funds Investment Income, Interest Realized gains on available-for-sale securities Available-for-sale Securities, Gross Realized Gains Realized losses on available-for-sale securities Available-for-sale Securities, Gross Realized Losses Gain on sale of assets Gain (Loss) on Disposition of Business Gain on sale of business Gain (Loss) on Disposition of Assets Gain on Sale of Investments Gain on Sale of Investments Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component Non-service components of pension expense, net Non-Service Component, Net Of Net Periodic Pension Expense Non-Service Component, Net Of Net Periodic Pension Expense Non-Service Component, Net Of Net Periodic Pension Expense Other (income)/expense, net Schedule Of Operating Leases Future Minimum Payments Due Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Amortization of Intangible Assets Amortization of Intangible Assets Weighted average remaining useful life Finite-Lived Intangible Asset, Useful Life Schedule of Business Combinations [Abstract] Schedule of Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Global Cash Card, Inc. [Member] Global Cash Card, Inc. [Member] Global Cash Card, Inc. [Member] Work Market, Inc. [Member] Work Market, Inc. [Member] Work Market, Inc. [Member] Celergo Holdings, Inc. [Member] Celergo Holdings, Inc. [Member] Celergo Holdings, Inc. [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Date of Acquisition Agreement Business Acquisition, Date of Acquisition Agreement Percentage of shares acquired Business Acquisition, Percentage of Voting Interests Acquired Acquisition Price Payments to Acquire Businesses, Gross Weighted Average Useful Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Identifiable intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Statement of Cash Flows [Abstract] Cash Flows from Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net earnings to cash flows provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Deferred income taxes Stock-based compensation expense Share-based Payment Arrangement, Noncash Expense Net pension expense Pension Cost (Reversal of Cost) Net amortization of premiums and accretion of discounts on available-for-sale securities Accretion (Amortization) of Discounts and Premiums, Investments Gain on sale of assets Gain (Loss) on Sale of Properties Gain on sale of divested businesses, net of tax Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal, net of Tax Amount after tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes Discontinued operations. Other Other Noncash Expense Changes in operating assets and liabilities, net of effects from acquisitions and divestitures of businesses: Increase (Decrease) in Operating Capital [Abstract] (Increase)/decrease in accounts receivable Increase (Decrease) in Accounts and Notes Receivable Increase in other assets Decrease in accounts payable Increase (Decrease) in Accounts Payable, Trade Increase in accrued expenses and other liabilities Net cash flows provided by operating activities Cash Flows from Investing Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of corporate and client funds marketable securities Payments to Acquire Marketable Securities Proceeds from the sales and maturities of corporate and client funds marketable securities Proceeds from Sale of Available-for-sale Securities Capital expenditures Payments to Acquire Other Property, Plant, and Equipment Additions to intangibles Payments to Acquire Intangible Assets Acquisitions of businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Proceeds from the sale of property, plant, and equipment and other assets Proceeds from Sale of Property, Plant, and Equipment Proceeds from the sale of divested businesses Proceeds from Divestiture of Businesses Net cash flows used in investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Net increase/(decrease) in client funds obligations Net decrease increase in client funds obligations Net (decrease) increase in client funds obligations Payments of debt Repayments of Long-term Debt Repurchases of common stock Payments for Repurchase of Common Stock Net proceeds from stock purchase plan and stock-based compensation plans Net Proceeds from stock purchase plan and stock based compensation plans Proceeds from stock plans, stock options exercises, and payments related to tax withholding for share-based compensation. Dividends paid Payments of Dividends Other Proceeds from (Payments for) Other Financing Activities Net cash flows used in financing activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash, cash equivalents, restricted cash, and restricted cash equivalents Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Net change in cash, cash equivalents, restricted cash, and restricted cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, cash equivalents, restricted cash, and restricted cash equivalents, beginning of year Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents, restricted cash, and restricted cash equivalents, end of year Restricted cash and restricted cash equivalents included in funds held for clients (A) Total cash, cash equivalents, restricted cash, and restricted cash equivalents Net proceeds from reverse repurchase agreements Net (repayments of)/proceeds from reverse repurchase agreements Net (repayments of)/proceeds from reverse repurchase agreements Cash paid for interest Interest Paid, Including Capitalized Interest, Operating and Investing Activities Cash paid for income taxes, net of income tax refunds Income Taxes Paid, Net Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Earliest Tax Year [Member] Earliest Tax Year [Member] Latest Tax Year [Member] Latest Tax Year [Member] INDIA INDIA WISCONSIN WISCONSIN MICHIGAN MICHIGAN Income Tax Examination [Line Items] Income Tax Examination [Line Items] Income Tax Examination, Year under Examination Income Tax Examination, Year under Examination Deferred Tax Assets, Net of Valuation Allowance, Current Deferred Tax Assets, Net of Valuation Allowance, Current Deferred Tax Liabilities, Net, Current Deferred Tax Liabilities, Net, Current Current Federal Tax Expense (Benefit) Current Federal Tax Expense (Benefit) Current Foreign Tax Expense (Benefit) Current Foreign Tax Expense (Benefit) Current State and Local Tax Expense (Benefit) Current State and Local Tax Expense (Benefit) Current Income Tax Expense (Benefit) Current Income Tax Expense (Benefit) Deferred Federal Income Tax Expense (Benefit) Deferred Federal Income Tax Expense (Benefit) Deferred Foreign Income Tax Expense (Benefit) Deferred Foreign Income Tax Expense (Benefit) Deferred State and Local Income Tax Expense (Benefit) Deferred State and Local Income Tax Expense (Benefit) Deferred Income Tax Expense (Benefit) Deferred Income Tax Expense (Benefit)