Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Net Income (Loss) Attributable to Parent Adjustments to reconcile net income (loss) to net cash used in operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Operating Lease, Impairment Loss Operating Lease, Impairment Loss Share-based compensation Share-based Compensation Amortization of debt discount and issuance costs Amortization of Debt Issuance Costs and Discounts Allowances For Doubtful Accounts And Unbilled Services Provision for Doubtful Accounts 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: Increase (Decrease) in Operating Capital [Abstract] (Increase) decrease in receivables from clients, net Increase (Decrease) in Accounts Receivable (Increase) decrease in unbilled services, net 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 other 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 used in 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 Purchases of businesses, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Capitalization of internally developed software costs Payments to Develop Software 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 exercise of stock options Proceeds from Stock Options Exercised Shares redeemed for employee tax withholdings Payments Related to Tax Withholding for Share-based Compensation Proceeds from borrowings under credit facility Proceeds from Long-term Lines of Credit Repayments of debt Repayments of Long-term Debt Payments of Debt Issuance Costs Payments of Debt Issuance Costs Net cash provided by 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: Noncash Investing and Financing Items [Abstract] Property and equipment expenditures and capitalized software included in accounts payable and accrued expenses Capital Expenditures Incurred but Not yet Paid Contingent consideration related to business acquisitions Business Combination, Contingent Consideration, Liability Fair Value Disclosures [Abstract] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Table] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Table] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] 1.25% convertible senior notes due 2019 Convertible Debt [Member] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Line Items] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Line Items] Carrying Amounts And Estimated Fair Values Of Financial Instruments [Line Items] Net carrying amount Long-term Debt Estimated Fair Value Long-term Debt, Fair Value Debt Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Senior secured credit facility 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, Current Maturities Long-term Debt, Current Maturities Long-term debt, net of current portion Long-term Debt, Excluding Current Maturities 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] Prepaid Expenses and Other Current Assets [Member] Prepaid Expenses and Other Current Assets [Member] Other Noncurrent Assets [Member] Other Noncurrent Assets [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 Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Estimated annual intangible assets amortization expense, Year Two Finite-Lived Intangible Assets, Amortization Expense, Year Two Estimated annual intangible assets amortization expense, Year Three Finite-Lived Intangible Assets, Amortization Expense, Year Three Estimated annual intangible assets amortization expense, Year Four Finite-Lived Intangible Assets, Amortization Expense, Year Four Estimated annual intangible assets amortization expense, Year Five 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 Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] 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 investment Convertible Debt Securities [Member] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Shorelight Holdings LLC Shorelight Holdings Llc [Member] Shorelight Holdings Llc [Member] 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] Fair Value of Financial Instruments [Abstract] Financial Instruments, Owned, at Fair Value [Abstract] Assets, fair value Assets, Fair Value Disclosure Investments in notes Long-term Investments Debt Instrument, Maturity Date Debt Instrument, Maturity Date Aggregate principal amount Debt Instrument, Face Amount Carrying value of equity component Debt Instrument, Convertible, Carrying Amount of Equity Component Closing price of common stock Share Price 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 Stock Repurchase Program, Remaining Authorized Repurchase Amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Financing Arrangements Debt Disclosure [Text Block] Equity [Abstract] Foreign currency translation adjustment, before taxes Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Foreign currency translation adjustment, taxes 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. Foreign currency translation adjustment, net of taxes Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Unrealized gain on investment, before taxes Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax Unrealized gain on investment, tax (expense) benefit Other Comprehensive Income (Loss), Available-for-sale Securities, Tax Unrealized gain on investment, net of taxes Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Change in fair value, before taxes Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax Change in fair value, tax (expense) benefit Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Change in fair value, net of taxes Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Reclassification adjustments into earnings, before taxes Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax Reclassification adjustments into earnings, tax (expense) benefit Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax Reclassification adjustments into earnings, net of taxes Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Net unrealized gain (loss), before taxes Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax, Portion Attributable to Parent Net unrealized gain (loss), tax (expense) benefit Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Portion Attributable to Parent Net unrealized gain (loss), net of taxes Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Other comprehensive income (loss), before taxes Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Other comprehensive income (loss), tax (expense) benefit Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Accumulated Other Comprehensive (Income) Loss, Current period change Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent New Accounting Pronouncements [Abstract] New Accounting Pronouncements [Abstract] Schedule of New Accounting Pronouncements and Changes in Accounting Principles Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Healthcare Health Care [Member] Healthcare. Education [Member] Education [Member] Education [Member] Business Advisory Business Advisory [Member] Business Advisory [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill Goodwill, Gross Accumulated impairment losses Goodwill, Impaired, Accumulated Impairment Loss Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill, net beginning balance Goodwill Goodwill, Foreign Currency Translation Gain (Loss) Goodwill, Foreign Currency Translation Gain (Loss) Goodwill, net ending balance Commitments and Contingencies Disclosure [Abstract] Commitments, Contingencies and Guarantees Commitments Contingencies and Guarantees [Text Block] 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] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest Rate Swap [Member] Interest Rate Swap [Member] Liability Class [Axis] Liability Class [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Contingent consideration for business acquisitions Contingent Consideration Liability [Member] Contingent Consideration Liability [Member] Liabilities: Liabilities, Fair Value Disclosure [Abstract] Fair Value, Asset/Liability Assets, Fair Value Disclosure [Abstract] Liabilities, fair value Financial and Nonfinancial Liabilities, Fair Value Disclosure Restructuring and Related Activities [Abstract] Restructuring Charges Restructuring and Related Activities Disclosure [Text Block] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2016-02 [Member] Accounting Standards Update 2016-02 [Member] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Employee Severance [Member] Employee Severance [Member] Office Space Reductions [Member] Office Space Reductions [Member] Office Space Reductions [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring reserve Restructuring Reserve New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Restructuring and Related Cost, Incurred Cost Restructuring and Related Cost, Incurred Cost Payments for Restructuring Payments for Restructuring Restructuring Reserve, Accrual Adjustment Restructuring Reserve, Accrual Adjustment Noncash Restructuring Adjustments Noncashrestructuringadjustments Adjustment to the amount of restructuring charges incurred in the period for noncash activities. New Accounting Pronouncements and Changes in Accounting Principles [Abstract] New Accounting Pronouncements New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Income Tax Disclosure [Abstract] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Adjustments for Error Corrections [Axis] Adjustments for Error Corrections [Axis] Adjustments for Error Correction [Domain] Adjustments for Error Correction [Domain] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Loss on continuing operations Foreign [Member] Loss on continuing operations Foreign [Member] Loss on continuing operations Foreign [Member] Executive Compensation [Member] Executive Compensation [Member] Executive Compensation [Member] Share-based Compensation [Member] Share-based Compensation [Member] Share-based Compensation [Member] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, Percent Income tax expense Income Tax Expense (Benefit) Income (loss) from continuing operations before taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Effective Income Tax Rate Reconciliation, at Statutory Rate, Inclusive of State Income Tax, Percent Statutory Income Tax Rate, Inclusive of State Income Tax, Percent Statutory Income Tax Rate, Inclusive of State Income Tax, Percent Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent Effective Income Tax Rate Reconciliation, Disallowed Executive Compensation, Percent Effective Income Tax Rate Reconciliation, Disallowed Executive Compensation, 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 Segment Reporting [Abstract] Components of Segment Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Segment Information Segment Reporting Disclosure [Text Block] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Corporate, Non-Segment [Member] Corporate, Non-Segment [Member] Huron Legal [Member] Huron Legal [Member] Huron Legal [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] Discontinued Operations [Member] Discontinued Operations [Member] Restructuring Charges [Abstract] Restructuring Charges [Abstract] Restructuring charges Restructuring Charges Restructuring and Related Cost, Accelerated Depreciation Restructuring and Related Cost, Accelerated Depreciation Leases [Abstract] Leases of Lessee Disclosure [Text Block] Leases of Lessee Disclosure [Text Block] Disaggregation of Revenue [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Fixed-price Contract [Member] Fixed-price Contract [Member] Time-and-materials Contract [Member] Time-and-materials Contract [Member] Performance-based [Member] Performance-based [Member] Performance-based [Member] Software Service, Support and Maintenance Arrangement [Member] Software Service, Support and Maintenance Arrangement [Member] Employee Type [Axis] Employee Type [Axis] Employee Type [Axis] Employee Type [Domain] Employee Type [Domain] [Domain] for Employee Type [Axis] Full-time Billable Consultants [Member] Full-time Billable Consultants [Member] Full-time Billable Consultants [Member] Full-time Equivalents [Member] Full-time Equivalents [Member] Full-time Equivalents [Member] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Transferred over Time [Member] Transferred over Time [Member] Transferred at Point in Time [Member] Transferred at Point in Time [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Sales Revenue, Services, Net Sales Revenue, Services, Net 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 Derivative Instruments and Hedging Activity Derivative Instruments and Hedging Activities Disclosure [Text Block] Line of Credit Facility [Table] Line of Credit Facility [Table] Convertible Senior Notes [Line Items] Convertible Senior Notes [Line Items] Convertible Senior Notes [Line Items] Proceeds Less: debt discount, net of amortization Debt Instrument, Unamortized Discount Debt Issuance Costs, Net Debt Issuance Costs, Net Net carrying amount Equity component Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Accounting Policies [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Earnings Per Share, Policy Earnings Per Share, Policy [Policy Text Block] Convertible Senior Notes, Policy Accounting For Convertible Senior Notes [Policy Text Block] Disclosure of accounting policy for convertible senior notes including the process of calculating the debt discount and related treatment of the equity and liability components. Derivatives and Hedging, Policy Derivatives, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy Fair Value of Financial Instruments, Policy [Policy Text Block] Segment Reporting, Policy Segment Reporting, Policy [Policy Text Block] Lessee, Leases, Policy Lessee, Leases [Policy Text Block] Fair Value Disclosures - Contingent Consideration Reconciliation [Abstract] Fair Value Disclosures - Contingent Consideration Reconciliation [Abstract] Change in Fair Value, Reason [Axis] Change in Fair Value, Reason [Axis] Change in Fair Value, Reason [Axis] Change in Fair Value, Reason [Domain] Change in Fair Value, Reason [Domain] [Domain] for Change in Fair Value, Reason [Axis] Foreign Currency Gain (Loss) [Member] Foreign Currency Gain (Loss) [Member] Fair Value, Measurements, Recurring [Member] Financial and Nonfinancial Liabilities, Fair Value Disclosure Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease) Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease) Statement of Comprehensive Income [Abstract] Revenues and reimbursable expenses: Revenues [Abstract] Revenues Reimbursable expenses Reimbursement Revenue Total revenues and reimbursable expenses Revenues Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses): Direct Operating Costs [Abstract] Direct costs Cost of Services Amortization of intangible assets and software development costs Cost of Services, Depreciation and Amortization Reimbursable expenses Cost of Reimbursable Expense Total direct costs and reimbursable expenses Cost of Revenue Operating expenses and other losses (gains), net Operating Expenses [Abstract] Selling, general and administrative expenses 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 Depreciation, Depletion and Amortization, Nonproduction Total operating expenses and other losses (gains), net Operating Expenses Operating income 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 income (expense), net Other Nonoperating Income (Expense) Total other expense, net Nonoperating Income (Expense) Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent 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 earnings (loss) per basic share: Income (Loss) from Continuing Operations, Per Basic 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 Basic (USD per share) Earnings Per Share, Basic Net earnings per diluted share: Earnings Per Share, Diluted [Abstract] Income (Loss) from Continuing Operations, Per Diluted 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 Earnings Per Share, Diluted Earnings Per Share, Diluted Weighted average shares used in calculating earnings per share: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average common shares outstanding – basic Weighted Average Number of Shares Outstanding, Basic Weighted average common shares outstanding – diluted Weighted Average Number of Shares Outstanding, Diluted Comprehensive income (loss): Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Foreign currency translation adjustments, net of tax Unrealized gain on investment, net of tax Unrealized gain (loss) on cash flow hedging instruments, net of tax Other comprehensive income Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Basis of Presentation Basis of Accounting [Text Block] Description of Business Nature of Operations [Text Block] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Aircraft [Domain] Aircraft [Domain] Note Hedge Note Hedge [Member] Note Hedge [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Warrants related to the issuance of convertible senior notes Warrant [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR London Interbank Offered Rate (LIBOR) [Member] Base Rate [Member] Base Rate [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Debt instrument maturity date Debt Conversion, Original Debt, Due Date of Debt 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 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 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 Number of consecutive business days following consecutive trading days Debt instrument, Convertible, Threshold of Consecutive Business Days Following Consecutive Trading Days Debt instrument, Convertible, Threshold of Consecutive Business Days Following Consecutive Trading Days 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 Debt Instrument, Convertible, Remaining Discount Amortization Period Debt Instrument, Convertible, Remaining Discount Amortization Period 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 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 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 tax liability Deferred Tax Liabilities, Net, Noncurrent Deferred tax asset Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Revolving Credit facility 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. Credit agreement expiration date Line of Credit Facility, Expiration Date Option to increase revolving credit facility Optional Increase In Revolver Optional increase in revolver. Maximum principle amount Line of Credit Facility, Maximum Borrowing Capacity Interest rate on borrowings Debt Instrument, Basis Spread on Variable Rate 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 other equity interests 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 other equity interests 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. Debt Instrument, Covenant, Consolidated Leverage Ratio, Minimum Debt Instrument, Covenant, Consolidated Leverage Ratio, Minimum Debt Instrument, Covenant, Consolidated Leverage Ratio, Minimum Maximum consolidated leverage ratio Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum Minimum consolidated 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 Percentage of weighted average interest rate of borrowings Debt, Weighted Average Interest Rate Outstanding letters of credit Letters of Credit Outstanding, Amount Unused borrowing capacity under Credit Agreement Line of Credit Facility, Remaining Borrowing Capacity Repayment of Principal at Maturity Date Repayment of Principal at Maturity Date Repayment of Principal at Maturity Date Duration of LIBOR Duration Of Libor The duration of LIBOR which is used to calculate the interest received from the counterparty. Property and equipment, net Property, Plant and Equipment, Net Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Weighted average common stock equivalents Weighted Average Number Diluted Shares Outstanding Adjustment Weighted average common shares outstanding – diluted Net earnings (loss) per basic share: Earnings Per Share, Basic and Diluted [Abstract] Basic (USD per share) Diluted (USD per share) 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 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 Gain (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 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] Interest Expense, Debt, Excluding Amortization Interest Expense, Debt, Excluding Amortization Amortization of Debt Discount (Premium) Amortization of Debt Discount (Premium) Amortization of Debt Issuance Costs Amortization of Debt Issuance Costs Interest Expense, Debt Interest Expense, Debt Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Performance Obligation Satisfied in Prior Period [Axis] Performance Obligation Satisfied in Prior Period [Axis] Performance Obligation Satisfied in Prior Period [Axis] Performance Obligation Satisfied in Prior Period [Domain] Performance Obligation Satisfied in Prior Period [Domain] [Domain] for Performance Obligation Satisfied in Prior Period [Axis] Release of Allowance [Member] Release of Allowance [Member] Release of Allowance [Member] Change in Estimated Variable Consideration [Member] Change in Estimated Variable Consideration [Member] Change in Estimated Variable Consideration [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Contract with Customer, Performance Obligation Satisfied in Previous Period Contract with Customer, Performance Obligation Satisfied in Previous Period Revenue, Remaining Performance Obligation Revenue, Remaining Performance Obligation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 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 Convertible 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. 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] Unvested restricted stock awards Restricted Stock [Member] Employee Stock Option [Member] Employee Stock Option [Member] Convertible senior notes 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 Number of Operating Segments Number of Operating Segments Components of Other Comprehensive Income (Loss), Net of Tax Comprehensive Income (Loss) [Table Text Block] Components of Accumulated Other Comprehensive Income (Loss), Net of Tax Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Commitments And Contingencies [Table] Commitments And Contingencies [Table] Commitments And Contingencies [Table] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Guarantees in the form of letters of credit Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Accounting Standards Update 2014-09 [Member] Accounting Standards Update 2014-09 [Member] Common Stock Common Stock [Member] Treasury Stock Treasury Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) 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, shares Shares, Issued Beginning Balance Stockholders' Equity Attributable to Parent 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, shares Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Restricted stock awards, net of cancellations Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Stock Issued During Period, Value, Stock Options Exercised Stock Issued During Period, Value, Stock Options Exercised Share-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Shares redeemed for employee tax withholdings, shares Shares Paid for Tax Withholding for Share Based Compensation Shares redeemed for employee tax withholdings Adjustments Related to Tax Withholding for Share-based Compensation Ending Balance, shares Ending Balance Operating Lease, Right-of-Use Asset Operating Lease, Right-of-Use Asset Operating Lease, Liability, Current Operating Lease, Liability, Current Operating Lease, Liability, Noncurrent Operating Lease, Liability, Noncurrent Operating Lease, Liability Operating Lease, Liability Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Financial Assets and Liabilities Measured at Fair Value on Recurring Basis 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] Summary of Carrying Amount and Estimated Fair Value of Convertible Senior Notes Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Operating Lease, Payments Operating Lease, Payments Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Discount Rate, Percent Operating Lease, Weighted Average Discount Rate, Percent Amortization of Intangible Assets Amortization of Intangible Assets Earnings Per Share Earnings Per Share [Text Block] Statement of Financial Position [Abstract] Common stock, par value (USD per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (shares) Common Stock, Shares Authorized Common stock, shares issued (shares) Common Stock, Shares, Issued Treasury stock, shares (shares) Treasury Stock, Shares Foreign Currency Translation Adjustments, Beginning balance Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Foreign Currency Translation Adjustments, Ending balance Net Unrealized Gain (Loss) on Investment, Beginning balance Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Net Unrealized Gain (Loss) on Investment, Ending balance Net Unrealized Losses on Derivatives, Beginning balance Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Net Unrealized Losses on Derivatives, Ending balance Accumulated Other Comprehensive Income (Loss), Beginning balance Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Ending balance Fair Value Disclosures - Convertible Debt Investment Reconciliation [Abstract] Fair Value Disclosures - Convertible Debt Investment Reconciliation [Abstract] Shorelight Holdings Llc [Member] Assets, Fair Value Disclosure 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) Schedule of Supplemental Balance Sheet Information for Operating Leases Schedule of Supplemental Balance Sheet Information for Operating Leases [Table Text Block] Schedule of Supplemental Balance Sheet Information for Operating Leases [Table Text Block] Lease, Cost Lease, Cost [Table Text Block] Lessee, Operating Lease, Liability, Maturity Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Supplemental Operating Lease Information Schedule of Supplemental Operating Lease Information [Table Text Block] [Table Text Block] for Schedule of Supplemental Operating Lease Information [Table] Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Liability, Payments, Due Imputed interest of lease liabilities Lessee Operating Lease Liability Undiscounted Excess Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease. Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Change in Contract with Customer, Asset [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] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Change in Contract with Customer, Asset and Liability [Abstract] Contract with Customer, Asset, Net Contract with Customer, Asset, Net Contract Asset, Period Increase (Decrease) Contract Asset, Period Increase (Decrease) Amount of increase (decrease) in the right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than the passage of time. Deferred revenues Deferred Revenue, Current Increase (decrease) in deferred revenues Deferred Revenue, Period Increase (Decrease) Deferred Revenue, Revenue Recognized Deferred Revenue, Revenue Recognized 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] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Operating lease right-of-use asset [Member] Operating lease right-of-use asset [Member] Operating lease right-of-use asset [Member] Leasehold Improvements [Member] Leasehold Improvements [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Lessee, Operating Lease, Lease Not yet Commenced, Description Lessee, Operating Lease, Lease Not yet Commenced, Description Operating Leases, Future Minimum Payments Receivable Operating Leases, Future Minimum Payments Receivable Operating Leases, Rent Expense, Net Operating Leases, Rent Expense, Net Lessee, Operating Lease, Renewal Term Lessee, Operating Lease, Renewal Term Impact of Adoption - Balance Sheet [Abstract] Impact of Adoption - Balance Sheet [Abstract] Accrued Liabilities [Member] Accrued Liabilities [Member] Current maturities of operating lease liabilities [Domain] Operating lease liability current [Member] Operating lease liability current [Member] Other Liabilities [Member] Other Liabilities [Member] Deferred lease incentives [Domain] Deferred rent credit noncurrent [Member] Deferred rent credit noncurrent [Member] Operating lease liabilities, net of current [Domain] Operating lease liability noncurrent [Member] Operating lease liability noncurrent [Member] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Domain] Adjustments for Change in Accounting Principle [Domain] Receivables from clients, net Accounts Receivable, Net, Current Costs in Excess of Billings, Current Costs in Excess of Billings, Current Income tax receivable Income Taxes Receivable, Current Deferred Tax Assets, Net, Noncurrent Deferred Tax Assets, Net, Noncurrent Other non-current assets Other Assets, Noncurrent Accrued payroll and related benefits Employee-related Liabilities, Current Retained earnings Retained Earnings (Accumulated Deficit) 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). Operating lease liabilities, net of current portion Deferred Rent Credit, Noncurrent 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] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Assets Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Prepaid Expense and Other Assets, Current Prepaid Expense and Other Assets, Current Total current assets Assets, Current Long-term investment Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Total assets 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 Business Combination, Contingent Consideration, Liability, Current Business Combination, Contingent Consideration, Liability, Current Long-term Debt, Current Maturities Total current liabilities Liabilities, Current Non-current liabilities: Liabilities, Noncurrent [Abstract] Business Combination, Contingent Consideration, Liability, Noncurrent Business Combination, Contingent Consideration, Liability, Noncurrent Deferred income taxes, net Total non-current liabilities Liabilities, Noncurrent Commitments and contingencies Commitments and Contingencies Stockholders’ equity Stockholders' Equity Attributable to Parent [Abstract] Common stock Common Stock, Value, Issued Treasury stock Treasury Stock, Value Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated other comprehensive income Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity 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 Operating Segments [Member] Segment Reconciling Items Segment Reconciling Items [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Components of Segment Information Segment Reporting Information, Profit (Loss) [Abstract] Operating income (loss) Segment operating income as a percentage of segment revenues Operating Income Loss As Percent Of Revenues Segment operating income (loss) as percent of segment revenues. Total revenues and reimbursable expenses Other operating expenses Other Selling, General and Administrative Expense Other expense, net Income from continuing operations before income tax expense 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 Fair Value of Financial Instruments Fair Value Disclosures [Text Block] 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 Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Customer Relationships [Member] Customer Relationships [Member] Trade Names [Member] Trade Names [Member] Technology And Software [Member] Technology And Software [Member] Technology And Software [Member] Noncompete Agreements [Member] Noncompete Agreements [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 Operating Lease, Cost Operating Lease, Cost Short-term Lease, Cost Short-term Lease, Cost Variable Lease, Cost Variable Lease, Cost Sublease Income Sublease Income Lease, Cost Lease, Cost Income Taxes Income Tax Disclosure [Text Block] Schedule of Restructuring Reserve by Type of Cost Schedule of Restructuring Reserve by Type of Cost [Table Text Block]