Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Property, Plant and Equipment [Abstract] Depreciation expense for property and equipment Depreciation Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Liability Class [Axis] Liability Class [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Contingent Consideration Liability [Member] Contingent Consideration Liability [Member] Contingent Consideration Liability [Member] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Convertible Debt Securities [Member] Convertible Debt Securities [Member] Debt Security [Axis] Debt Security [Axis] Major Types of Debt Securities [Domain] Major Types of Debt Securities [Domain] Promissory Note [Member] Promissory Note [Member] Promissory note. Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Restructuring and Related Activities [Abstract] 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 Costs [Member] Employee Costs [Member] Employee Costs [Member] Office Space Reductions [Member] Office Space Reductions [Member] Office Space Reductions [Member] Other Restructuring [Member] Other Restructuring [Member] Restructuring Charges [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Restructuring reserve, period start Restructuring Reserve Restructuring additions Increase (Decrease) in Restructuring Reserve Payments for restructuring Payments for Restructuring Restructuring reserve adjustments Restructuring Reserve, Accrual Adjustment Noncashrestructuringadjustments Noncashrestructuringadjustments Adjustment to the amount of restructuring charges incurred in the period for noncash activities. Restructuring reserve, period end Debt Disclosure [Abstract] 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] Convertible Debt [Member] Convertible Debt [Member] Senior Secured Credit Facility [Member] Senior Secured Credit Facility [Member] Senior Secured Credit Facility [Member] Promissory Note due 2024 [Member] Promissory Note due 2024 [Member] Promissory Note due 2024 [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Long-term debt Long-term Debt Long-term Debt, Current Maturities Long-term Debt, Current Maturities Long-term debt, net of current portion Long-term Debt, Excluding Current Maturities Valuation and Qualifying Accounts [Abstract] Summary of Allowances for Doubtful Accounts and Unbilled Services and Valuation Allowance for Deferred Tax Assets Schedule Of Valuation And Qualifying Accounts Reserves Table [Text Block] A schedule of allowance and reserve accounts including their beginning and ending balances, as well as a reconciliation by type of activity during the period. Equity [Abstract] Capital Structure Stockholders' Equity Note Disclosure [Text Block] Business Combinations [Abstract] Business Combination, Separately Recognized Transactions [Table] Business Combination, Separately Recognized Transactions [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Innosight Holdings, LLC [Member] Innosight Holdings, LLC [Member] Innosight Holdings, LLC [Member] Studer Group Studer Group [Member] Studer Group [Member] Business Combination, Separately Recognized Transactions [Line Items] Business Combination, Separately Recognized Transactions [Line Items] Business acquisition, pro forma revenue Business Acquisition, Pro Forma Revenue Business acquisition, pro forma net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Business acquisition, pro forma earnings per share, basic (in USD per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Business acquisition, pro forma earnings per share, diluted (in USD per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Commitments and Contingencies Disclosure [Abstract] Future Minimum Rental Commitments Under Non-Cancelable Leases and Sublease Income Lease Minimum Future Obligation And Minimum Future Receivable Under Sublease Table [Text Block] Tabular disclosure of future minimum payments required in the aggregate and for each of the five succeeding fiscal years for capital leases and operating leases having initial or remaining noncancelable lease terms in excess of one year and the the total minimum rentals to be received in the future under noncancelable subleases, and as of the balance sheet date. Earnings Per Share Reconciliation [Abstract] Net income (loss) from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Net income (loss) Net Income (Loss) Attributable to Parent Weighted average common shares outstanding-basic Weighted Average Number of Shares Outstanding, Basic Weighted average common stock equivalents Weighted Average Number Diluted Shares Outstanding Adjustment Weighted average common shares outstanding- diluted Weighted Average Number of Shares Outstanding, Diluted Net earnings per basic share: Earnings Per Share, Basic [Abstract] Net income from continuing operations, per basic share (in USD per share) Income (Loss) from Continuing Operations, Per Basic Share Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share Net income, per basic share (in USD per share) Earnings Per Share, Basic Net earnings per diluted share: Earnings Per Share, Diluted [Abstract] Net income from continuing operations, per diluted share (in USD per share) Income (Loss) from Continuing Operations, Per Diluted Share Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share Net income, per diluted share (in USD per share) Earnings Per Share, Diluted Goodwill and Intangible Assets Disclosure [Abstract] Changes in Carrying Amount of Goodwill Schedule of Goodwill [Table Text Block] 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] Segment Reporting [Abstract] Components of Segment Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Segment Assets Reconciliation of Assets from Segment to Consolidated [Table Text Block] Commitments, Contingencies and Guarantees Commitments Contingencies and Guarantees [Text Block] Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income (loss) 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 Share-based compensation Share-based Compensation Amortization of debt discount and issuance costs Amortization of Debt Issuance Costs and Discounts Goodwill, Impairment Loss Goodwill, Impairment Loss Allowances for doubtful accounts and unbilled services Allowances For Doubtful Accounts And Unbilled Services Changes to allowance for doubtful accounts and unbilled services to an amount that approximates their net realizable value (the amount expected to be collected). Deferred income taxes Deferred Income Taxes and Tax Credits (Gain) loss on sale of businesses Gain (Loss) on Disposition of Business Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Changes in operating assets and liabilities, net of acquisitions and divestitures: Increase (Decrease) in Operating Capital [Abstract] (Increase) decrease in receivables from clients Increase (Decrease) in Accounts Receivable (Increase) decrease in unbilled services Increase (Decrease) in Unbilled Receivables (Increase) decrease in current income tax receivable / payable, net Increase (Decrease) in Income Taxes Payable, Net of Income Taxes Receivable (Increase) decrease in other assets Increase (Decrease) in Other Operating Assets Increase (decrease) in accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Increase (decrease) in accrued payroll and related benefits Increase (Decrease) in Employee Related Liabilities Increase (decrease) in deferred revenues Increase (Decrease) in Deferred Revenue Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment, net Payments to Acquire Property, Plant, and Equipment Investment in life insurance policies Payments for (Proceeds from) Life Insurance Policies Proceeds from Life Insurance Policies Proceeds from Life Insurance Policies Purchases of businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Purchases of convertible debt investment Payments to Acquire Available-for-sale Securities, Debt Capitalization of internally developed software Payments to Develop Software Proceeds from note receivable Proceeds from Sale and Collection of Notes Receivable Proceeds from Divestiture of Businesses Payments for (Proceeds from) Businesses and Interest in Affiliates Net 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 [Abstract] Proceeds from exercises of stock options Proceeds from Stock Options Exercised Shares redeemed for employee tax withholdings Payments Related to Tax Withholding for Share-based Compensation Share repurchases Proceeds from (Repurchase of) Equity Proceeds from borrowings under credit facility Proceeds from Long-term Lines of Credit Repayments of debt Repayments of Long-term Debt Payments for debt issuance costs Payments of Debt Issuance Costs Payments for capital lease obligations Repayments of Long-term Capital Lease Obligations Deferred acquisition payments Payment of Contingent Consideration Liabilities Payment of Contingent Consideration Liabilities Net cash provided by (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 Net decrease in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of the period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of the period Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Non-cash investing and financing activities: Non Cash InvestingFinancing Activities [Abstract] Non Cash Investing and Financing Activities [Abstract] Property and equipment expenditures included in accounts payable and accrued expenses Capital Expenditures Incurred but Not yet Paid Notes Assumed Notes Assumed Contingent consideration related to business acquisitions Business Combination, Contingent Consideration, Liability Common stock issued related to business acquisitions Stock Issued Cash paid during the year for: Cash Paid During Year For [Abstract] Cash paid during year for. Interest Interest Paid Income taxes Income Taxes Paid Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Long-term Debt, Maturities, Repayments of Principal in Year Two Long-term Debt, Maturities, Repayments of Principal in Year Two Long-term Debt, Maturities, Repayments of Principal in Year Three Long-term Debt, Maturities, Repayments of Principal in Year Three Long-term Debt, Maturities, Repayments of Principal in Year Four Long-term Debt, Maturities, Repayments of Principal in Year Four Long-term Debt, Maturities, Repayments of Principal in Year Five Long-term Debt, Maturities, Repayments of Principal in Year Five Long-term Debt, Maturities, Repayments of Principal after Year Five Long-term Debt, Maturities, Repayments of Principal after Year Five Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Two Thousand And Twelve Plan [Member] Two Thousand And Twelve Plan [Member] Two Thousand And Twelve Plan [Member] Stock Ownership Participation Program [Member] Stock Ownership Participation Program [Member] Stock Ownership Participation Program [Member] Two Thousand and Four Plan [Member] Two Thousand and Four Plan [Member] Two Thousand and Four Plan [Member] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Executive Officer [Member] Executive Officer [Member] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Domain] Option Indexed to Issuer's Equity, Type [Domain] Employee Stock Option [Member] Employee Stock Option [Member] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Restricted Stock Awards [Member] Restricted Stock [Member] Performance-based stock activity [Member] Performance Shares [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Increase in number of shares authorized for issuance Share Based Compensation Arrangement By Share Based Payment Award Plan Modification Increase In Authorized Shares Share Based Compensation Arrangement By Share Based Payment Award Plan Modification Increase In Authorized Shares Shares available for issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Restricted stock granted as a percentage of purchased shares Share-Based Compensation Arrangement By Share-Based Payment Award, Restricted Stock Granted, As A Percentage Of Purchased Shares Share-Based Compensation Arrangement By Share-Based Payment Award, Restricted Stock Granted, As A Percentage Of Purchased Shares Retirement eligible provision, description Retirement Eligible Provision Description A narrative description of the retirement eligible provision adopted under the share based payment plan. Retirement eligible provision, minimum age Retirement Eligible Provision Minimum Age Retirement Eligible Provision Minimum Age Retirement eligible provision, minimum years of service Retirement Eligible Provision Minimum Term Of Service Retirement eligible provision minimum term of service. Share-based compensation expense Allocated Share-based Compensation Expense Income tax benefits Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Unrecognized compensation cost Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized compensation cost, Period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Stock option awards granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Stock options contractual term Share Based Compensation Arrangement By Share Based Payment Award Expiration Period One The contractual term of stock options, after which the stock options will expire. Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Aggregate fair value of stock vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Weighted average grant date fair value (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Exercise of stock options, shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures Disposal Groups, Including Discontinued Operations [Table Text Block] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Groups, Including Discontinued Operations, Name [Domain] Disposal Group Name [Domain] Discontinued operations [Member] Discontinued Operations [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Huron Legal [Member] Huron Legal [Member] Huron Legal [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 Group, Including Discontinued Operation, Assets Disposal Group, Including Discontinued Operation, Assets Disposal Group, Including Discontinued Operation, Consideration Disposal Group, Including Discontinued Operation, Consideration Loss on disposal Disposal Group, Including Discontinued Operation, Liabilities Disposal Group, Including Discontinued Operation, Liabilities Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] 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] Computers, related equipment and software [Member] Computers Related Equipment And Software [Member] Computers Related Equipment And Software [Member] Leasehold Improvements [Member] Leasehold Improvements [Member] Furniture and fixtures [Member] Furniture and Fixtures [Member] Assets under Construction [Member] Asset under Construction [Member] Aircraft [Domain] Aircraft [Domain] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property and equipment Property, Plant and Equipment, Gross Accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Property, Plant and Equipment, Net Acquisitions Business Combination Disclosure [Text Block] Amortization of intangible assets and software development costs Depreciation and Amortization, Discontinued Operations Purchases of property and equipment Significant non-cash investing items of discontinued operations: Noncash Investing and Financing Items [Abstract] Contingent consideration related to business acquisitions Contingent Consideration Transaction Value Related To Business Acquisition The value of the contingent consideration given in a business acquisition that is not payable until a future period. Derivative Instruments and Hedging Activities Disclosure [Abstract] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other Noncurrent Assets [Member] Other Noncurrent Assets [Member] Accrued expenses [Member] Accrued Liabilities [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Fair Value interest rate swaps designated as cash flow hedging instruments Interest Rate Cash Flow Hedge Derivative at Fair Value, Net [Abstract] Fair value (derivative asset and liability) Interest Rate Cash Flow Hedge Derivative at Fair Value, Net Income Tax Disclosure [Abstract] Net Income Tax Benefit Recognized from Intercompany Receivable Write Off Net Income Tax Benefit Recognized from Intercompany Receivable Write Off The recognized net tax benefit from the one-time "check-the-box" election to treat a wholly owned foreign subsidiary as a disregarded entity. At U.S. statutory tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent Meals and entertainment Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment, Percent Valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Foreign source income Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Tax credits / Section 199 Deduction Effective Income Tax Rate Reconciliation, Tax Credit, Percent Net tax (benefit) expense related to “check-the-box” election (1) Effective Income Tax Rate Reconciliation Net Tax Benefit Related to Check the Box Election Effective Income Tax Rate Reconciliation Net Tax Benefit Related to Check the Box Election Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective income tax expense rate for continuing operations Effective Income Tax Rate Reconciliation, Percent Document And Entity Information [Abstract] Document and entity information. Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Public Float Entity Public Float Schedule of Restructuring Reserve by Type of Cost Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Valuation and Qualifying Accounts Disclosure [Table] Valuation and Qualifying Accounts Disclosure [Table] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves [Domain] Valuation Allowances and Reserves [Domain] Allowances for doubtful accounts and unbilled services [Member] Allowance for Doubtful Accounts [Member] Valuation allowance for deferred tax assets [Member] Valuation Allowance of Deferred Tax Assets [Member] Valuation and Qualifying Accounts Disclosure [Line Items] Valuation and Qualifying Accounts Disclosure [Line Items] Beginning balance Valuation Allowances and Reserves, Balance Additions Valuation Allowances and Reserves, Additions for Charges to Cost and Expense Deductions Valuation Allowances and Reserves, Deductions Ending balance Earnings Per Share [Abstract] Accelerated Share Repurchases [Table] Accelerated Share Repurchases [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Share Repurchase Program [Member] Share Repurchase Program [Member] Share Repurchase Program [Member] Accelerated Share Repurchases [Line Items] Accelerated Share Repurchases [Line Items] Share repurchase authorized amount Stock Repurchase Program, Authorized Amount Shares repurchased Stock Repurchased and Retired During Period, Shares Stock Repurchased and Retired During Period, Value Stock Repurchased and Retired During Period, Value Stock Repurchase Program, Remaining Authorized Repurchase Amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Prepaid Expenses and Other Current Assets [Member] Prepaid Expenses and Other Current Assets [Member] Accounting Advisory Practice [Member] Accounting Advisory Practice [Member] The Accounting Advisory Practice of a consulting group which has been sold for non-cash or part non-cash transaction. Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Shorelight Holdings Llc [Member] Shorelight Holdings Llc [Member] Shorelight Holdings Llc [Member] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] Non Cash Consideration For Sale Of Discontinued Operation Non Cash Consideration For Sale Of Discontinued Operation The face value of the promissory note received for the sale of discontinued operations. Note Receivable, Term Note Receivable, Term Note Receivable, Term Reduction in Principal of Amended Promissory Note Reduction in Principal of Amended Promissory Note Reduction in Principal of Amended Promissory Note Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Held-to-maturity Securities, Debt Maturities, Date Held-to-maturity Securities, Debt Maturities, Date Fair Value Inputs, Discount Rate Fair Value Inputs, Discount Rate Assets, Fair Value Disclosure Assets, Fair Value Disclosure Long-term Investments Long-term Investments Debt Instrument, Maturity Date Debt Instrument, Maturity Date Aggregate principal amount Debt Instrument, Face Amount Debt Instrument, Convertible, Carrying Amount of Equity Component Debt Instrument, Convertible, Carrying Amount of Equity Component Share Price Share Price Promissory Note, Principal, Outstanding Promissory Note, Principal, Outstanding Promissory Note, Principal, Outstanding Other Comprehensive Income (Loss), Net of Tax [Abstract] Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Tax Amount of tax expense (benefit) related to, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Other Comprehensive Income (Loss), Available-for-sale Securities, Tax Other Comprehensive Income (Loss), Available-for-sale Securities, Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Warrant [Member] Warrant [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Total anti-dilutive securities Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Health Care [Member] Health Care [Member] Healthcare. Education [Member] Education [Member] Education [Member] Business Advisory [Member] Business Advisory [Member] Business Advisory [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill Goodwill, Gross Accumulated impairment losses Goodwill, Impaired, Accumulated Impairment Loss Goodwill, net beginning balance Goodwill Goodwill recorded in connection with business combinations Goodwill, Acquired During Period Goodwill, Impairment Loss Goodwill, Transfers Goodwill, Transfers Goodwill, Written off Related to Sale of Business Unit Goodwill, Written off Related to Sale of Business Unit Foreign currency translation Goodwill, Foreign Currency Translation Gain (Loss) Goodwill, net ending balance Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Foreign currency translation adjustments, beginning balance Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax Foreign currency translation adjustments, ending balance Foreign currency translation adjustment, net of tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Reclassification adjustment, net of tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax Unrealized loss on investment, beginning balance Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Unrealized loss on investments Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Other Comprehensive Income (Loss), Available for Sale Investment, Unrealized gain (loss) Other Comprehensive Income (Loss), Available for Sale Investment, Unrealized gain (loss) Other Comprehensive Income (Loss), Available for Sale Investment, Unrealized gain (loss) Unrealized loss on investment, ending balance Unrealized gain (loss) on cash flow hedges, beginning balance Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Change in fair value Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Reclassification adjustment into earnings Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Unrealized gain (loss) on cash flow hedges, ending balance Accumulated other comprehensive loss, beginning balance Accumulated Other Comprehensive Income (Loss), Net of Tax Change in fair value Reclassification adjustment into earnings Accumulated other comprehensive loss, ending balance Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest Rate Swap [Member] Interest Rate Swap [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Retained Earnings [Member] Retained Earnings [Member] Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses) Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses) New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments [Member] Operating Segments [Member] Segment Reconciling Items [Member] Segment Reconciling Items [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Segment Assets: Segment Reporting Information, Additional Elements for Bank Presentation [Abstract] Total assets Assets Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Line Items] Business Acquisition [Line Items] Payments to Acquire Businesses, Gross Payments to Acquire Businesses, Gross Acquisition date fair value Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Consideration transferred net working capital adjustment Business Combination Consideration Transferred Net Working Capital Adjustment Business combination consideration transferred net working capital adjustment. Acquisition date fair value of the consideration Business Combination, Consideration Transferred Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Amortization of Intangible Assets Amortization of Intangible Assets Finite-Lived Intangible Assets, Amortization Expense, Year Two Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Finite-Lived Intangible Assets, Amortization Expense, Year Three Finite-Lived Intangible Assets, Amortization Expense, Year Two Finite-Lived Intangible Assets, Amortization Expense, Year Four Finite-Lived Intangible Assets, Amortization Expense, Year Three Finite-Lived Intangible Assets, Amortization Expense, Year Five Finite-Lived Intangible Assets, Amortization Expense, Year Four Finite-Lived Intangible Assets, Amortization Expense, after Year Five Finite-Lived Intangible Assets, Amortization Expense, Year Five U.S. Income (Loss) from Continuing Operations before Income Taxes, Domestic Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Income (loss) from continuing operations before taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Fair value measurement policy Fair Value Measurement, Policy [Policy Text Block] Schedule of Restricted Stock Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Schedule of Performance-Based Stock Activity Schedule of Nonvested Performance-based Units Activity [Table Text Block] Schedule of Stock Option Activity Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Income Taxes Income Tax Disclosure [Text Block] Components of Accumulated Other Comprehensive Loss, Net of Tax Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Total current Current Income Tax Expense (Benefit) Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Foreign Deferred Foreign Income Tax Expense (Benefit) Total deferred Deferred Income Tax Expense (Benefit) Income tax expense for continuing operations Income Tax Expense (Benefit) Commitments And Contingencies [Table] Commitments And Contingencies [Table] Commitments And Contingencies [Table] Fair Value, Inputs, Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Chicago, Illinois [Member] Chicago, Illinois [Member] Chicago, Illinois [Member] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Lease Expiration Date Lease Expiration Date Period of renewal option that allow continue to occupy the majority of office space Lessee Leasing Arrangements, Operating Leases, Renewal Term Rental expense, including operating costs and taxes Operating Leases, Rent Expense, Net Guarantees in the form of letters of credit Letters of Credit Outstanding, Amount Financial and Nonfinancial Liabilities, Fair Value Disclosure Financial and Nonfinancial Liabilities, Fair Value Disclosure Renewal Option, Expiration Date Renewal Option, Expiration Date Renewal Option, Expiration Date Quarterly Financial Information Disclosure [Abstract] Revenues Sales Revenue, Services, Net Reimbursable expenses Reimbursement Revenue Total revenues and reimbursable expenses Revenues Gross profit Gross Profit Operating income (loss) Operating Income (Loss) Weighted average shares used in calculating earnings per share: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (shares) Diluted (shares) Estimated fair value Long-term Debt, Fair Value Description of Business Nature of Operations [Text Block] Fair Value Disclosures - 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Other operating expenses and gains Other Selling, General and Administrative Expense Gain (Loss) Related To Litigation Settlement And Other Operating Gains Gain (Loss) Related To Litigation Settlement And Other Operating Gains Amount of (gain) loss recognized in settlement of litigation and insurance claims and other operating activities. Also includes the amount of increase (decrease) in the fair value of a contingent consideration liability, including, but not limited to, differences arising upon settlement. Depreciation and amortization expense Depreciation, Depletion and Amortization, Nonproduction Other expense, net Nonoperating Income (Expense) Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Domain] Type of Adoption [Domain] ASU201609 [Member] ASU201609 [Member] ASU201609 [Member] ASU2018-02 [Member] ASU2018-02 [Member] ASU2018-02 [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Treasury Stock [Member] Treasury Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance Stockholders' Equity Attributable to Parent Beginning balance, shares Shares, Issued Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Share-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Issuance of common stock in connection with: Issuance Of Common Stock In Connection With [Abstract] Issuance Of Common Stock In Connection With [Abstract] Restricted stock awards, net of cancellations Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Restricted stock awards, net of cancellations, shares Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Stock Issued During Period, Value, Stock Options Exercised Stock Issued During Period, Value, Stock Options Exercised Business acquisition Stock Issued During Period, Value, Acquisitions Business acquisition, shares Stock Issued During Period, Shares, Acquisitions Shares redeemed for employee tax withholdings Adjustments Related to Tax Withholding for Share-based Compensation Shares redeemed for employee tax withholdings, shares Shares Paid for Tax Withholding for Share Based Compensation Income tax benefit on share-based compensation Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Share repurchases Share repurchases, shares Ending balance Ending balance, shares Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Goodwill, Impairment Loss [Member] Goodwill, Impairment Loss [Member] Goodwill, Impairment Loss [Member] Adjustments for Error Corrections [Axis] Adjustments for Error Corrections [Axis] Adjustments for Error Correction [Domain] Adjustments for Error Correction [Domain] MyRounding [Member] MyRounding [Member] MyRounding [Member] Reporting Unit [Axis] Reporting Unit [Axis] Reporting Unit [Axis] Reporting Unit [Domain] Reporting Unit [Domain] [Domain] for Reporting Unit [Axis] Enterprise Solutions and Analytics [Member] Enterprise Solutions and Analytics [Member] Enterprise Solutions and Analytics [Member] Strategy and Innovation [Member] Strategy and Innovation [Member] Strategy and Innovation [Member] Life Sciences [Member] Life Sciences [Member] Life Sciences [Member] 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] Technology-Based Intangible Assets [Member] Technology And Software [Member] Technology And Software [Member] In Process Research and Development [Member] In Process Research and Development [Member] Goodwill, Written off Related to Sale of Business Unit Error Corrections and Prior Period Adjustments, Description Error Corrections and Prior Period Adjustments, Description Reporting Unit, Percentage of 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and Administrative Expense Restructuring charges (1) Restructuring Charges Litigation and other losses (gains), net Depreciation and amortization Total operating expenses and other losses (gains), net Operating Expenses Operating income (loss) Other income (expense), net Nonoperating Income (Expense) [Abstract] Interest Expense Net Of Interest Income Interest Expense Net Of Interest Income The cost of borrowed funds accounted for as interest that was charged against earnings during the period, net of immaterial amounts of interest income recognized during the period associated with banking, investing or other activities. Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Nonoperating Income (Expense) Income tax expense (benefit) Net income (loss) from continuing operations Net income (loss) Net income, per basic share (in USD per share) Net income, per diluted share (in USD per share) Comprehensive income (loss): Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Foreign currency translation adjustments, net of tax Unrealized gain (loss) on investment, net of tax Unrealized gain (loss) on cash flow hedging instruments, net of tax Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Postemployment Benefits [Abstract] Employer contributions up to percent of employee's salaries Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Employer matching contributions Defined Contribution Plan, Employer Discretionary Contribution Amount Deferred compensation liability Deferred Compensation Liability, Current and Noncurrent Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Unrecognized tax benefits, beginning balance Unrecognized Income Tax Benefits Unrecognized Income Tax Benefits Decrease based on tax positions related to the prior year Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Additions based on tax positions related to the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Unrecognized tax benefits, ending balance Derivative Instruments and Hedging Activity Derivative Instruments and Hedging Activities Disclosure [Text Block] Reconciliation of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Summary of Anti-dilutive Securities Excluded from Computation of Weighted Average Common Stock Equivalents Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Statement of Financial Position [Abstract] Common stock, par value (in USD 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, Issued Treasury stock, shares Treasury Stock, Shares Quarterly Financial Information [Table Text Block] Quarterly Financial Information [Table Text Block] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Effect of Fourth Quarter Event Type [Axis] Effect of Fourth Quarter Event Type [Axis] Effect of Fourth Quarter Events, Type [Domain] Effect of Fourth Quarter Events, Type [Domain] Remeasurement of deferred tax balances [Member] Remeasurement of deferred tax balances [Member] Remeasurement of deferred tax balances [Member] Transition tax on accumulated foreign earnings [Member] Transition tax on accumulated foreign earnings [Member] Transition tax on accumulated foreign earnings [Member] Elimination of foreign credits on repatriation of foreign earnings as dividends [Member] Elimination of foreign credits on repatriation of foreign earnings as dividends [Member] Elimination of foreign credits on repatriation of foreign earnings as dividends [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Foreign[Member] Foreign Tax Authority [Member] State and Local Jurisdiction [Member] State and Local Jurisdiction [Member] Federal [Member] Domestic Tax Authority [Member] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Income Tax Expense (Benefit) Additional Income Tax Expense due to Tax Reform Additional Income Tax Expense due to Tax Reform Realizable income tax benefit from check-the-box election Realizable Tax Benefit from Intercompany Receivable Write Off The realizable tax benefit expected from the one-time "check-the-box" election to treat a whole owned foreign subsidiary as a disregarded entity. Unrecognized tax benefit from check-the-box election Unrecognized Tax Benefit from Intercompany Receivable Write Off The unrealized tax benefit from our one-time "check-the-box" election to treat a wholly owned foreign subsidiary as a disregarded entity. Effective tax rates for discontinued operations Effective Tax Rate For Discontinued Operations Effective Tax Rate For Discontinued Operations Tax benefit (expense) Discontinued Operation, Tax Effect of Discontinued Operation Income from discontinued operations before taxes Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Valuation allowance Deferred Tax Assets, Valuation Allowance Federal and state tax credit carry forwards Tax Credit Carryforward, Amount Tax credit carry forward expiration year Tax Credit Carry Forward Expiration Year Tax credit carry forward expiration year. Income tax year is subject future examinations by federal tax authorities and local tax authorities Income Tax Examination Period Income Tax Examination Period Unrecognized Income Tax Benefits Income Tax Examination, Penalties and Interest Accrued Income Tax Examination, Penalties and Interest Accrued Schedule of Property and Equipment Property, Plant and Equipment [Table Text Block] Interest rate swap agreement, effective date Derivative, Inception Date Interest rate swap agreement, end date Derivative, Maturity Date Interest rate swap agreement for a notional amount Derivative, Notional Amount Duration of LIBOR Duration Of Libor The duration of LIBOR which is used to calculate the interest received from the counterparty. Percentage of fixed rate Interest Rate Swap Fixed Interest Rate The fixed interest rate we pay to the counterparty of the interest rate swap. Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred Loss reclassification from accumulated OCI to income, estimate of time to transfer Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimate of Time to Transfer Income Taxes Income Tax Uncertainties, Policy [Policy Text Block] Number of billing arrangements for revenue recognition Number Of Billing Arrangements For Revenue Recognition The number of billing arrangements the Company uses on client engagements. The nature of each arrangement will help determine the appropriate revenue recognition for that engagement. Schedule of Cash and Cash Equivalents [Table] Schedule of Cash and Cash Equivalents [Table] Incorrect netting of deferred tax assets and deferred tax liabilities [Member] Incorrect netting of deferred tax assets and deferred tax liabilities [Member] Incorrect netting of deferred tax assets and deferred tax liabilities [Member] Income Tax Expense [Member] Income Tax Expense [Member] Income Tax Expense [Member] Goodwill [Member] Goodwill [Member] Deferred Tax Asset [Domain] Deferred Tax Asset [Domain] Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Depreciated over and estimated useful life Property, Plant and Equipment, Estimated Useful Lives Cash and Cash Equivalent maturity period Cash And Cash Equivalent Maturity Period The maximum length of time over which an instrument may mature to be classified as cash and cash equivalents. Unamortized capitalized software development costs Capitalized Software Development Costs for Software Sold to Customers Amortized capitalized software development costs Capitalized Computer Software, Amortization Impairment of long-lived assets Impairment of Long-Lived Assets Held-for-use Impairment of intangible assets and goodwill Goodwill and Intangible Asset Impairment Number of Reporting Units Number of Reporting Units Number of Operating Segments Number of Operating Segments Deferred lease incentives Deferred Rent Credit, Noncurrent Sponsorship and advertising costs Marketing and Advertising Expense Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Foreign currency translation gain (loss), net of tax Foreign Currency Transaction Gain (Loss), Realized Note Hedge [Member] Note Hedge [Member] Note Hedge [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] Base Rate [Member] Base Rate [Member] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Scenario One, Leverage Ratio [Member] Scenario One, Leverage Ratio [Member] Scenario One, Leverage Ratio [Member] Scenario Two, Leverage Ratio [Member] Scenario Two, Leverage Ratio [Member] Scenario Two, Leverage Ratio [Member] Debt Instrument, Unamortized Discount Debt Instrument, Unamortized Discount Debt Issuance Costs, Net Debt Issuance Costs, Net Number of common shares converted upon debt conversion for each $1000 principal amount Debt Instrument, Convertible, Conversion Ratio Principal amount of notes per conversion Principal Amount Per Note The principal, or par, value of each note issued. Conversion price of convertible notes (in USD per share) Debt Instrument, Convertible, Conversion Price Optional right of debt instrument holders to convert debt instrument into cash, portion of principal amount Percentage Of Principal Paid Upon Exercise Of Put Percentage of principal amount required to be paid upon a debt holder's exercise of the put option following a fundamental change as defined in the indenture. Earliest conversion date Debt Instrument Convertible Date The earliest date on which the debt instrument can be converted into equity if none of the other conversion conditions have been met. Number of least trading days required within 30 consecutive trading days Debt Instrument, Convertible, Threshold Consecutive Trading Days Number of consecutive trading days Number Of Consecutive Period Of Trading Number of consecutive trading days during the last month of the preceding quarter in which the closing price on 20 such days must meet the stock price threshold defined in the indenture. Percentage of applicable conversion price Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger Concentration risk percentage Minimum Trading Price Percentage The minimum trading price as a percentage of the product of the last reported share price and the conversion rate of the notes. Effective interest rate of debt Debt Instrument, Interest Rate, Effective Percentage Remaining life of notes Debt Instrument, Convertible, Remaining Discount Amortization Period Payments of Debt Issuance Costs Liability issuance costs Debt Issuance Costs Assigned To Liability Total debt issuance costs assigned to the liability component of the convertible senior notes based on the relative fair value of the liability component to the total value of the notes issued. Equity issuance costs Issuance Costs Assigned To Equity Total issuance costs assigned to the equity component of the convertible senior notes based on the relative fair value of the equity component to the total value of the notes issued. Common stock purchased (in shares) Common Stock Underlying Convertible Senior Note And Related Transactions The number of shares of common stock underlying the convertible senior notes as well as the warrants and convertible note hedge transactions purchased concurrently with the issuance of the convertible senior notes. Aggregate amount for convertible hedge Payments For Note Hedges The cash outflow associated with the amount paid for convertible senior note hedges. Common stock price (in USD per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Aggregate proceeds from the sale of warrants Proceeds from Issuance of Warrants Deferred income taxes, net Deferred Tax Liabilities, Net, Noncurrent Deferred tax asset Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Line of credit current borrowing capacity Line of Credit Facility, Current Borrowing Capacity Period of revolving credit facility Period Of Revolving Credit Facility Period of time between issuance and maturity of the revolving credit facility. Maturity date Line of Credit Facility, Expiration Date Optional increase In revolver Optional Increase In Revolver Optional increase in revolver. Aggregate principal amount - Senior secured credit facility Line of Credit Facility, Maximum Borrowing Capacity Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Required payment on revolver related to convertible debt maturity term Required Payment On Revolver Related To Convertible Debt Maturity Term Required payment on revolver related to convertible debt maturity term. Percentage of pledged voting stock in domestic subsidiaries Percentage Of Pledged Voting Stock In Domestic Subsidiaries The percentage of pledged voting stock or other equity instruments in the domestic subsidiaries to secure the revolver and term loan. Percentage of pledged voting stock in foreign subsidiaries Percentage Of Pledged Voting Stock In Foreign Subsidiaries The percentage of pledged voting stock or other equity instruments in the foreign subsidiaries to secure the revolver and term loan. Maximum consolidated leverage ratio Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum Minimum interest coverage ratio Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Actual consolidated leverage ratio Debt Instrument, Covenant, Actual Consolidated Leverage Ratio Debt Instrument, Covenant, Actual Consolidated Leverage Ratio Actual interest coverage ratio Debt Instrument, Covenant, Actual Interest Coverage Ratio Debt Instrument, Covenant, Actual Interest Coverage Ratio Repayment of Principal at Maturity Date Repayment of Principal at Maturity Date Repayment of Principal at Maturity Date Percentage of weighted average interest rate of borrowings Debt, Weighted Average Interest Rate Outstanding letters of credit Unused borrowing capacity under Credit Agreement Line of Credit Facility, Remaining Borrowing Capacity Property and equipment, net Debt Conversion, Original Debt, Due Date of Debt Debt Conversion, Original Debt, Due Date of Debt Income Tax Expense for Continuing Operations Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Components of Income from Continuing Operations Before Income Tax Expense Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Reconciliation of Statutory Income Tax Rate to Our Effective Tax Rate for Continuing Operations Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Net Deferred Tax Liabilities for Continuing Operations Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns Roll Forward [Table Text Block] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Summary of Fair Value of Consideration Transferred Schedule Of Fair Value Of Consideration Received [Table Text Block] Schedule Of Fair Value Of Consideration Received [Table Text Block] Preliminary Allocation of the Purchase Price to the Fair Value of Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Components of Identifiable Intangible Assets Acquired and their Estimated Useful Lives Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Summary of Supplemental Pro Forma Consolidated Results of Operations Business Acquisition, Pro Forma Information [Table Text Block] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Costs in Excess of Billings, Current Costs in Excess of Billings, Current Prepaid expenses and other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Deferred income tax asset Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets, Current Property and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Accrued expenses and other current liabilities Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Accrued Liabilities And Other Liabilities Current Business combination recognized identifiable assets acquired and liabilities assumed accrued liabilities and other liabilities current. Accrued payroll and related benefits Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Current Liabilities Accrued Payroll and Benefits Business combination recognized identifiable assets acquired and liabilities assumed current liabilities accrued payroll and benefits. Deferred revenues Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Deferred income tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent Other non-current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities Total identifiable net assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Goodwill Total purchase price Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Line of Credit Facility [Table] Line of Credit Facility [Table] Convertible Senior Notes [Line Items] Line of Credit Facility [Line Items] Proceeds Less: debt discount, net of amortization Long-term debt Equity component Fair Value Interest Rate Swaps Designated as Cash Flow Hedging Instruments Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Restructuring Charges Restructuring and Related Activities Disclosure [Text Block] Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Derivatives, Policy [Policy Text Block] Derivatives, Policy [Policy Text Block] Basis of Presentation and Principles of Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Allowances for Doubtful Accounts and Unbilled Services Receivables, Policy [Policy Text Block] Direct Costs and Reimbursable Expenses Cost of Sales, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Concentrations of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Investments Marketable Securities, Available-for-sale Securities, Policy [Policy Text Block] Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Software Development Costs Research, Development, and Computer Software, Policy [Policy Text Block] Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Business Combinations Business Combinations Policy [Policy Text Block] Deferred Lease Incentives Lease, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Share-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Sponsorship and Advertising Costs Advertising Costs, Policy [Policy Text Block] Debt Issuance Costs Debt, Policy [Policy Text Block] Foreign Currency Foreign Currency Transactions and Translations Policy [Policy Text Block] Segment Reporting Segment Reporting, Policy [Policy Text Block] New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Customer contracts [Member] Customer Contracts [Member] Customer relationships [Member] Customer Relationships [Member] Non-competition Agreements [Member] Noncompete Agreements [Member] Trade names [Member] Trade Names [Member] Publishing content [Member] Publishing Content [Member] Publishing Content [Member] Off-Market Favorable Lease [Member] Off-Market Favorable Lease [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Intangible assets Finite-Lived Intangible Assets, Net [Abstract] Useful life in years Finite-Lived Intangible Asset, Useful Life Gross carrying amount Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Indefinite-Lived Intangible Assets (Excluding Goodwill) Indefinite-Lived Intangible Assets (Excluding Goodwill) Financing Arrangements Debt Disclosure [Text Block] Summary of Carrying Amounts of Debt Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Maturities of Long-term Debt Schedule of Maturities of Long-term Debt [Table Text Block] Schedule of Notes Convertible Debt [Table Text Block] Summary of Interest Expense Recognized Interest Expense Disclosure [Table Text Block] Tabular disclosure of components of interest expense recognized during the period related to the convertible senior notes. Components of interest expense include the contractual interest coupon, the amortization of debt issuance costs, and the amortization of the debt discount. Sales [Member] Sales [Member] Cost of Sales [Member] Cost of Sales [Member] Operating Expense [Member] Operating Expense [Member] Operating Income (Loss) [Member] Operating Income (Loss) [Member] Facility Closing [Member] Facility Closing [Member] One-time Termination Benefits [Member] One-time Termination Benefits [Member] Employee Severance [Member] Employee Severance [Member] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Sale of Huron Legal [Member] Sale Of Huron Legal [Member] Sale Of Huron Legal [Member] Revenues Disposal Group, Including Discontinued Operation, Revenue Reimbursable expenses Disposal Group, Including Discontinued Operation, Reimbursable Expenses Disposal Group, Including Discontinued Operation, Reimbursable Expenses Total revenues and reimbursable expenses Direct costs Disposal Group, Including Discontinued Operation, Costs of Goods Sold Reimbursable expenses Selling, general and administrative expenses Disposal Group, Including Discontinued Operation, General and Administrative Expense Other gain Disposal Group, Including Discontinued Operation, Gains (Losses) Disposal Group, Including Discontinued Operation, Gains (Losses) Depreciation and amortization Disposal Group, Including Discontinued Operation, Depreciation and Amortization Total operating expenses and other operating gain Disposal Group, Including Discontinued Operation, Operating Expense Operating income Disposal Group, Including Discontinued Operation, Operating Income (Loss) Total operating expenses and other operating gains Other expense, net Disposal Group, Including Discontinued Operation, Other Expense Total loss from discontinued operations before taxes Income tax benefit (2) Scenario, Forecast [Member] Scenario, Forecast [Member] Nonvested performance-based shares outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Nonvested And Unearned Performance Shares Nonvested And Unearned Performance Shares As of the balance sheet date, the number of shares included in the non-vested balance that are still in their performance period or whose earned percentage has not yet been determined. Forfeited, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Interest Expense Recognized [Table] Interest Expense Recognized [Table] Interest Expense Recognized [Table] Interest Expense Recognized [Line Items] Interest Expense Recognized [Line Items] [Line Items] for Interest Expense Recognized [Table] Contractual interest coupon Interest Expense, Debt, Excluding Amortization Amortization of debt discount Amortization of Debt Discount (Premium) Amortization of debt issuance costs Amortization of Debt Issuance Costs Total interest expense recognized Interest Expense, Debt Fair Value Disclosures - Convertible Debt Investment Reconciliation [Abstract] Fair Value Disclosures - Convertible Debt Investment Reconciliation [Abstract] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Underlying Asset Class [Axis] Underlying Asset Class [Axis] Underlying Asset Class [Domain] Underlying Asset Class [Domain] Deferred Compensation Plan Assets [Member] Deferred Compensation Plan Assets [Member] Deferred Compensation Plan Assets [Member] Liabilities, Fair Value Disclosure [Abstract] Liabilities, Fair Value Disclosure [Abstract] Assets, Fair Value Disclosure [Abstract] Assets, Fair Value Disclosure [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Excess Tax Benefit from Share-based Compensation, Financing Activities Excess Tax Benefit from Share-based Compensation, Financing Activities Stock-based compensation forfeiture allowance Stock-Based Compensation Forfeiture Allowance Stock-Based Compensation Forfeiture Allowance Equity Incentive Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Deferred tax assets: Components of Deferred Tax Assets [Abstract] Share-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Accrued payroll and other liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Deferred Tax Assets, Goodwill and Intangible Assets Deferred Tax Assets, Goodwill and Intangible Assets Deferred lease incentives Deferred Tax Assets Current Deferred Lease Incentive Amount before allocation of valuation allowances of deferred tax assets attributable to deductible temporary differences from deferred lease incentives. Revenue recognition Deferred Tax Assets Revenue Recognition Amount before allocation of valuation allowances of deferred tax assets attributable to deductible temporary differences from revenue recognition. Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Restructuring Charges Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Restructuring Charges Net operating loss carry-forwards Deferred Tax Assets, Operating Loss Carryforwards Tax credits Deferred Tax Assets, Tax Credit Carryforwards Deferred Tax Assets, Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Valuation allowance Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Convertible note hedge transactions Deferred Tax Assets, Hedging Transactions Deferred tax liabilities: Components of Deferred Tax Liabilities [Abstract] Prepaid expenses Deferred Tax Liabilities, Prepaid Expenses Property and equipment Deferred Tax Liabilities, Property, Plant and Equipment Intangibles and goodwill Deferred Tax Liabilities, Goodwill and Intangible Assets Convertible note discount Deferred Tax Liabilities Convertible Note Discount Deferred tax liabilities convertible note discount. Deferred Tax Liabilities, Investments Deferred Tax Liabilities, Investments Other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Gross Deferred Tax Assets, Net Deferred Tax Assets, Net Net deferred tax liability for continuing operations Deferred Tax Liabilities, Net Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Nonvested stock, number of shares, beginning balance Granted, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Nonvested stock, number of shares, ending balance Weighted Average Grant Date Fair Value (in dollars) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Nonvested stock, weighted average grant date fair value, beginning balance (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Vested, weighted average grant date fair value (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited, weighted average grant date fair value (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Nonvested stock, weighted average grant date fair value, ending balance (in USD per share) Total Weighted Average Grant Date Fair Value (in dollars) Segment Information Segment Reporting Disclosure [Text Block] Earnings Per Share Earnings Per Share [Text Block] Healthcare and Business Advisory [Member] Healthcare and Business Advisory [Member] Healthcare and Business Advisory [Member] Corporate, Non-Segment [Member] Corporate, Non-Segment [Member] Other Segments [Member] Restructuring additions Restructuring charge liability Employee Benefit and Deferred Compensation Plans Compensation and Employee Benefit Plans [Text Block] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Receivables from clients, net Accounts Receivable, Net, Current Income tax receivable Income Taxes Receivable, Current Prepaid Expense and Other Assets, Current Prepaid Expense and Other Assets, Current Total current assets Assets, Current Deferred Tax Assets, Net, Noncurrent Deferred Tax Assets, Net, Noncurrent Long-term investment Other non-current assets Other Assets, Noncurrent Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Total assets Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued expenses and other current liabilities Accrued Liabilities, Current Accrued payroll and related benefits Employee-related Liabilities, Current Business Combination, Contingent Consideration, Liability, Current Business Combination, Contingent Consideration, Liability, Current Deferred revenues Deferred Revenue, Current Total current liabilities Liabilities, Current Non-current liabilities: Liabilities, Noncurrent [Abstract] Deferred compensation and other liabilities Deferred Compensation And Other Liabilities Aggregate carrying value, as of the balance sheet date, of the liabilities for all deferred compensation arrangements and all other non current obligations not separately disclosed in the balance sheet payable beyond one year (or the operating cycle, if longer). Business Combination, Contingent Consideration, Liability, Noncurrent Business Combination, Contingent Consideration, Liability, Noncurrent Total non-current liabilities Liabilities, Noncurrent Commitments and contingencies Commitments and Contingencies Stockholders’ equity Stockholders' Equity Attributable to Parent [Abstract] Common Stock, Value, Issued Common Stock, Value, Issued Treasury Stock, Value Treasury Stock, Value Additional paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity Number of Options (in thousands) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding, shares, beginning balance Forfeited or expired, shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding, shares, ending balance Exercisable, shares, ending balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted Average Exercise Price (in dollars) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance, weighted average exercise price (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Ending balance, weighted average exercise price (in USD per share) Exercisable, weighted average exercise price (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted-average remaining contractual term (years), option outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted-average remaining contractual term (years), options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate intrinsic value, option outstanding, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate intrinsic value, option outstanding, ending balance Aggregate intrinsic value, options exercisable, ending balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares approved or issued Preferred Stock, Shares Issued