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Restricted stock issued Stock Issued During Period, Shares, Restricted Stock Award, Gross Rental expense for facilities and equipment leases Operating Leases, Rent Expense Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Property and equipment, net of accumulated depreciation of $7,395 and $6,462 Net property and equipment Property, Plant and Equipment, Net Expenses: Costs and Expenses [Abstract] Level 2 Fair Value, Inputs, Level 2 [Member] Trust [Member] Trust [Member] Trust. 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Gross Unrealized Gains Trading Securities, Unrealized Holding Gain Trading Securities, Unrealized Holding Gain Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Weighted-Average Grant Date Fair Value for Shares Granted and the Total Fair Value of Shares Vested Share Based Compensation Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value And Fair Value Of Shares Vested Table [Text Block] Share based compensation award equity instruments other than options grants in period weighted average grant date fair value and fair value of shares vested. 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Service period of mutual fund share incentive award Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period Net deferred tax assets and liabilities are reflected on our balance sheet Deferred Tax Assets, Net, Classification [Abstract] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Tax Reform [Axis] Tax Reform [Axis] Tax Reform [Axis] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Variable Interest Entities Schedule of Variable Interest Entities [Table Text Block] Change in uncertain tax positions, net of federal income taxes, effective tax rate Effective Income Tax Rate Reconciliation, Tax Contingency, Domestic, Percent Deferred tax assets: Deferred Tax Assets, Net [Abstract] Basic (in shares) Weighted average shares outstanding – basic (in shares) Weighted Average Number of Shares Outstanding, Basic Intangible assets, net Net Carrying Amount Finite-Lived Intangible Assets, Net U.S. Government and Government agency obligations US Treasury and Government [Member] Customer [Domain] Customer [Domain] Schedule Of Significant Accounting Policies [Line Items] Schedule Of Significant Accounting Policies [Line Items] Schedule of significant accounting policies. Entity Public Float Entity Public Float Westwood Funds Westwood Funds [Member] Westwood funds. 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Issuance of common stock for acquisition, shares Stock Issued During Period, Shares, Acquisitions Performance​ Based​ Restricted​ Shares​ For Future Performance Years Performance Based Restricted Shares For Future Performance Years [Member] Performance​ based​ restricted​ shares​ for future performance years. 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Long Term Investments, Cost, in a private company. Long Term Investments, Cost, in a private company. Share-based Compensation Award, Tranche One Share-based Payment Arrangement, Tranche One [Member] Segments [Axis] Segments [Axis] Adoption of ASU 2016-09 [Member] Adoption of ASU 2016-09 [Member] Adoption of ASU 2016-09 [Member] Subsequent Event Type Subsequent Event Type [Axis] Mutual Fund Advisory [Member] [Member] Mutual Fund Advisory [Member] [Member] Mutual Fund Advisory [Member] [Member] Non Cash Accrued PP&E Non Cash Accrued PP&E Non Cash Accrued PP&E Tax Reform [Table] Tax Reform [Table] Tax Reform [Table] Computer hardware and office equipment Computer Hardware And Office Equipment [Member] Computer hardware and office equipment. 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Document Transition Report Document Transition Report Sales Revenue, Net Revenue Benchmark [Member] Lease, Cost Lease, Cost [Table Text Block] Vested, shares Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vesting Vesting [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] Interest income – trading Interest and Dividend Income, Securities, Operating, Trading or Measured at Fair Value Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Restricted stock returned for payment of taxes Payment, Tax Withholding, Share-based Payment Arrangement Change in ASC 740-10 positions (net) Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Total expenses Operating Expenses Schedule Of Related Party Transactions By Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Dilutive potential shares from contingent consideration (in shares) Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares Reductions for tax positions related to prior years Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Woodway Financial Advisors Woodway Financial Advisors [Member] Woodway financial advisors. Property and Equipment Property, Plant and Equipment [Table Text Block] Accounts Receivable Receivable [Policy Text Block] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Income (loss) before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Related Party Transaction [Line Items] Related Party Transaction [Line Items] Property Plant And Equipment [Line Items] Property, Plant and Equipment [Line Items] Gain (Loss) Related to Litigation Settlement Gain (Loss) Related to Litigation Settlement Difference between the Federal corporate tax rate and the effective tax rate Effective Income Tax Rate Reconciliation, Amount [Abstract] Long Term Investment, at Cost, in Private Equity Long Term Investment, at Cost, in Private Equity Long Term Investment, at Cost, in Private Equity Stock-based compensation expense Restricted stock expense Share-based Payment Arrangement, Noncash Expense Document Annual Report Document Annual Report Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Closing sate consideration paid in cash Payments to Acquire Businesses, Gross Private Equity Investments [Member] Private Equity Investments [Member] Private Equity Investments [Member] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Axis] Operating Lease, Payments Operating Lease, Payments Geographical [Axis] Geographical [Axis] Accounts receivable Increase (Decrease) in Accounts Receivable Service condition restricted stock expense Restricted Shares Subject To Service Condition [Member] Restricted shares subject to service condition. Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Level 3 Fair Value, Inputs, Level 3 [Member] Date of incorporation Entity Incorporation, Date of Incorporation Lessee, Operating Lease, Disclosure Lessee, Operating Lease, Disclosure [Table Text Block] Tax Reform [Domain] Tax Reform [Domain] [Domain] for Tax Reform [Axis] Entity Address, City or Town Entity Address, City or Town Private Equity Investment Commitment Private Equity Investment Commitment Private Equity Investment Commitment Prepaid Taxes Prepaid Taxes Total income tax benefit recognized related to stock-based compensation Share-based Payment Arrangement, Expense, Tax Benefit Fees unpaid from related party Accounts Receivable, Related Parties, Current Estimated useful lives of the assets Property, Plant and Equipment, Useful Life Valuation allowance Deferred Tax Assets, Valuation Allowance Entity Filer Category Entity Filer Category Entity Voluntary Filers Entity Voluntary Filers Restatement [Domain] Restatement [Domain] Total payments due Operating Leases, Future Minimum Payments Due Future contractual rental payments for non-cancelable operating leases Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Common stock issued for acquisition Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Consolidation Items [Axis] Consolidation Items [Axis] Summary of Quarterly Results of Operations Quarterly Financial Information [Table Text Block] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Gain on sale of operations Other Operating Activities, Cash Flow Statement Subsequent Event [Table] Subsequent Event [Table] Total comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Statement [Line Items] Statement [Line Items] Non-cash accrued contingent consideration Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Cash dividends paid Payments of Dividends Number of operating segments Number of Reportable Segments Entity Registrant Name Entity Registrant Name Mutual Fund [Member] Mutual Fund [Member] Stock Repurchase Program, Authorized Amount Stock Repurchase Program, Authorized Amount Internally developed software Software and Software Development Costs [Member] Furniture and fixtures Furniture and Fixtures [Member] Treasury Stock Treasury Stock [Member] Weighted average shares outstanding: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Amendment Flag Amendment Flag Restricted Stock Subject Only to a Service Condition Restricted Stock Subject Only To Service Condition [Member] Restricted stock subject only to service condition. Additions for tax positions related to the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Maximum earn-out amount Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High Deferred taxes: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] City Area Code City Area Code Realized losses Trading Securities, Realized Loss Insurance Settlement [Member] Insurance Settlement [Member] Other Long-term Investments Other Long-term Investments Deferred tax liabilities: Deferred Tax Liabilities, Net [Abstract] Vesting Vesting [Axis] Minimum capital requirement Capital Required for Capital Adequacy Accrued Income Taxes, Noncurrent Accrued Income Taxes, Noncurrent Entity Central Index Key Entity Central Index Key Concentration Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Litigation Case Litigation Case [Domain] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Summary of Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Share-based Compensation Award, Tranche Three Share-based Payment Arrangement, Tranche Three [Member] Revenue Disaggregation by Geographic Location [Table Text Block] Revenue Disaggregation by Geographic Location [Table Text Block] [Table Text Block] for Revenue Disaggregation by Geographic Location [Table] Accounting Standards Update 2016-02 [Member] Accounting Standards Update 2016-02 [Member] Unrealized gain on private equity investment Unrealized gain on private equity investment Unrealized gain on private equity investment Advisory [Member] Advisory [Member] Advisory. Estimated lease asset and net lease liability for ASU 2016-02 Estimated lease asset and net lease liability for ASU 2016-02 Estimated lease asset and net lease liability for ASU 2016-02 Number of shares purchased in the open market Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award Common stock, shares authorized Common Stock, Shares Authorized Deferred Tax Assets and Deferred Tax Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Finite-Lived Intangible Assets, Accumulated Amortization Finite-Lived Intangible Assets Sold, Accumulated Amortization Finite-Lived Intangible Assets Sold, Accumulated Amortization Retained Earnings, Appropriated [Member] Retained Earnings, Appropriated [Member] Operating Lease, Lease Income, Lease Payments Operating Lease, Lease Income, Lease Payments Product and Service [Domain] Product and Service [Domain] Type of Adoption [Domain] Type of Adoption [Domain] Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Stock Repurchase Program, Remaining Authorized Repurchase Amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Restricted stock returned for payment of taxes, shares Restricted Stock, Shares Issued Net of Shares for Tax Withholdings Unrealized gains on investments Deferred Tax Liabilities, Unrealized Gains on Trading Securities Revenue From External Sources Revenue From External Sources Revenue From External Sources Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Mutual fund vesting period Share Based Compensation Arrangement With Individual Requisite Service Period Share based compensation arrangement with individual requisite service period. 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Entity Shell Company Entity Shell Company Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Fiduciary and Trust [Member] Fiduciary and Trust [Member] Deferred rent Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Deferred Rent Stock Based Compensation Share-based Payment Arrangement [Policy Text Block] Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] Total stockholders’ equity BALANCE BALANCE Stockholders' Equity Attributable to Parent Assets Under Management Assets under Management, Carrying Amount Other, net, effective tax rate Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Gross Carrying Amount Finite-Lived Intangible Assets, Gross Net realized gains (losses) Trading Securities, Realized Gain (Loss) Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Two Lawsuit filing date Loss Contingency, Lawsuit Filing Date Income (loss) before income taxes by jurisdiction Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest [Abstract] Plan Name [Axis] Plan Name [Axis] Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] VARIABLE INTEREST ENTITIES Variable Interest Entity Disclosure [Text Block] Investments Investments [Domain] Equity Component [Domain] Equity Component [Domain] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Related Party Transactions [Abstract] Related Party Transactions [Abstract] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Property and equipment cost Property, Plant and Equipment, Gross Westwood Holdings Group, Inc. Common Stock, Par Common Stock [Member] Finite-Lived Intangible Assets, Net Finite-Lived Intangible Assets Sold, Net Finite-Lived Intangible Assets Sold, Net Performance-based restricted stock expense Stock Based Compensation Expense Subject To Performance Condition [Member] Stock based compensation expense subject to performance condition. Restatement Adjustment [Member] Restatement Adjustment [Member] Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Investments, All Other Investments [Abstract] Investments, All Other Investments [Abstract] Geographical [Domain] Geographical [Domain] Schedule Of Available For Sale Securities [Table] Schedule of Available-for-sale Securities [Table] Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent First Lawsuit By A G F First Lawsuit By A G F [Member] First lawsuit by AGF. Other Revenue Gain (Loss) on Securities [Table Text Block] Institutional Institutional [Member] Institutional. Relationship to Entity Title of Individual [Domain] Accrued liability Mutual Fund Incentive Award Liability Mutual fund incentive award liability. Estimated useful lives of the assets Property, Plant and Equipment, Estimated Useful Lives Contingent consideration Business Combination, Contingent Consideration, Liability, Current Private investment fund Private Equity Funds, US [Member] Antidilutive Securities, Name Antidilutive Securities, Name [Domain] Customer [Axis] Customer [Axis] Current Fiscal Year End Date Current Fiscal Year End Date Percentage of Pretax income Goal Earned Percentage of Pretax income Goal Earned Percentage of Pretax income Goal Earned Private Wealth Advisory [Member] Private Wealth Advisory [Member] Private Wealth [Member] Treasury stock, shares Treasury Stock, Shares Effective Income Tax Rate Reconciliation, Tax Credit, Percent Effective Income Tax Rate Reconciliation, Tax Credit, Percent Effective Income Tax Rate Reconciliation, Tax Credit, Percent Professional services Professional Fees Restricted Stock Restricted Shares Subject Only to a Service Condition Restricted Stock [Member] Equity Award [Domain] Award Type [Domain] Accrued dividends Dividends Declared Dividends Declared Granted (in dollars per share) Weighted-average grant date fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Other Revenue, Net Other Revenue, Net Other Revenue, Net Additional paid-in capital Additional Paid in Capital, Common Stock Unrealized Gain (Loss) on Investments Unrealized Gain (Loss) on Investments Revenues by Geographic Location Revenue from External Customers by Geographic Areas [Table Text Block] General Damage General Damage [Member] General damage. Unrealized Gain (Loss) on Securities Unrealized Gain (Loss) on Securities Loss Contingencies [Table] Loss Contingencies [Table] Property and equipment, accumulated depreciation Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Loss contingency, receivable Loss Contingency, Receivable, Current Compensation and benefits payable Increase (Decrease) in Employee Related Liabilities Related Party Transaction, Purchases from Related Party Related Party Transaction, Purchases from Related Party Variable Interest Entities Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract] Components of accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Level 1 Fair Value, Inputs, Level 1 [Member] Difference between the Federal Corporate Tax Rate and the Effective Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Foreign Deferred Foreign Income Tax Expense (Benefit) General and Administrative Expense [Member] General and Administrative Expense [Member] CONCENTRATION Concentration Risk Disclosure [Text Block] Profit-sharing contributions Profit Sharing Contribution Profit sharing contribution. Income Statement Location [Axis] Income Statement Location [Axis] Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation [Axis] Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Reasonably possible maximum decrease in uncertain tax position Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Net Cash Provided by (Used in) Financing Activities Net Cash Provided by (Used in) Financing Activities Net Cash Provided by (Used in) Operating Activities Net Cash Provided by (Used in) Operating Activities Realized gains Trading Securities, Realized Gain Schedule Of Segment Reporting Information By Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Property and equipment Property, Plant and Equipment, Net [Abstract] Investment Type Investment Type [Axis] Sales and marketing Selling and Marketing Expense Treasury Stock Acquired, Average Cost Per Share Treasury Stock Acquired, Average Cost Per Share Currency Translation Foreign Currency Transactions and Translations Policy [Policy Text Block] Excess tax benefits from stock-based compensation Excess Tax Benefit from Share-based Compensation, Financing Activities Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Leasehold improvements Leasehold Improvements [Member] Operating Income (Loss) Operating Income (Loss) 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) Operating Lease, Liability Operating Lease, Liability Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Share Pretax Income Goal Sliding Scale Award Share Pretax Income Goal Sliding Scale Award Share Pretax Income Goal Sliding Scale Award Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months Deferred Tax Liabilities, Leasing Arrangements Deferred Tax Liabilities, Leasing Arrangements Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Penalties and interest Income Tax Examination, Penalties and Interest Expense Foreign Currency Transaction Gain (Loss), before Tax Foreign Currency Transaction Gain (Loss), before Tax Remaining unrecognized compensation cost recognized over a remaining weighted average period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Unrecognized deferred tax liability Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries Loss Contingencies [Line Items] Loss Contingencies [Line Items] Unrecognized tax benefits Federal unrecognized tax benefit Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Contingencies Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Retirement plan matching contributions Defined Contribution Plan, Employer Discretionary Contribution Amount Nonvested restricted shares (in shares) Non-vested, January 1, 2015 (in shares) Non-vested, December 31, 2015 (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Subsequent Event Subsequent Event [Member] Contract with Customer, Duration [Axis] Contract with Customer, Duration [Axis] Loss Contingency Nature Loss Contingency Nature [Axis] Investment balances Debt Securities, Trading, Restricted [Abstract] Compensation and benefits payable Employee-related Liabilities, Current Tax Reform [Line Items] Tax Reform [Line Items] [Line Items] for Tax Reform [Table] Percentage of defense costs which will be covered by insurance Percentage Of Defense Costs Covered By Insurance Percentage of defense costs covered by insurance. Westwood Management Westwood Management [Member] Westwood management. Future Contractual Rental Payments for Non-Cancelable Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Stock Issued During Period, Value, New Issues Stock Issued During Period, Value, New Issues Tax Credits used to pay Federal cash taxes Tax Credits used to pay Federal cash taxes Tax Credits used to pay Federal cash taxes 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Commitments and contingencies Commitments and Contingencies Schedule Of Finite Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Cover page. Variable Interest Entities [Abstract] Variable Interest Entities [Abstract] Variable interest entities. Income (Loss) Before Income Taxes by Jurisdiction Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] U.S. Federal Current Federal Tax Expense (Benefit) Total liabilities Liabilities Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] 2021 Operating Leases, Future Minimum Payments, Due in Three Years Lessee, Operating Lease, Liability, Undiscounted Excess Amount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Fair Value Hierarchy Including NAV [Domain] Fair Value Hierarchy Including NAV [Domain] [Domain] for Fair Value Hierarchy Including NAV [Axis] Trading Symbol Trading Symbol UNITED STATES U.S. UNITED STATES Basic (in dollars per share) Basic earnings per common share (in dollars per share) Earnings Per Share, Basic Document Period End Date Document Period End Date Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Four Unrecorded Unconditional Purchase Obligations Disclosure Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block] BALANCE SHEET COMPONENTS Supplemental Balance Sheet Disclosures [Text Block] Private equity Private Equity Funds [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Equity funds Equity Funds [Member] Finite-Lived Intangible Assets Disposed [Abstract] Finite-Lived Intangible Assets Disposed [Abstract] Finite-Lived Intangible Assets Disposed [Abstract] Europe [Member] Europe [Member] Westwood Holdings Corporate, Non-Segment [Member] Common stock, $0.01 par value, authorized 25,000,000 shares, issued 10,306,570 and outstanding 8,881,086 shares at December 31, 2019; issued 10,182,583 and outstanding 8,904,902 shares at December 31, 2018 Common Stock, Value, Issued Total deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Service, Other [Member] Service, Other [Member] Economic Earnings (Loss) Economic Earnings Losses Economic Earnings is a non-U.S. generally accepted accounting principles (“non-GAAP”) performance measure of segment profit or loss. We provide this measure in addition to, but not as a substitute for, net income, which is reported on a U.S. GAAP basis. Both our management and Board of Directors review Economic Earnings to evaluate our ongoing performance, allocate resources and review dividend policy. We believe that this non-GAAP performance measure of segment profit or loss, while not a substitute for GAAP net income, is useful for management and investors when evaluating our underlying operating and financial performance and our available resources. We do not advocate that investors consider this non-GAAP measure of segment profit or loss without considering financial information prepared in accordance with GAAP. Vesting period Defined Contribution Plan Specified Period Of Service For Employer Profit Sharing Contributions To Be Fully Vested Defined contribution plan specified period of service for employer profit sharing contributions to be fully vested. Issuance of common stock for acquisition Stock Issued During Period, Value, Acquisitions Restatement [Axis] Restatement [Axis] SUBSEQUENT EVENTS Subsequent Events [Text Block] Scenario, Unspecified [Domain] Scenario [Domain] Director Director [Member] Dividends declared per share Common Stock, Dividends, Per Share, Declared Stock-based compensation expense APIC, Share-based Payment Arrangement, Increase for Cost Recognition Revenues: Revenues [Abstract] Treasury stock, at cost – 1,425,483 shares at December 31, 2019; 1,277,681 shares at December 31, 2018 Treasury Stock, Value Assets Assets Estimated Amortization Expense for Intangible Assets over the Next Five Years Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Total long-term liabilities Liabilities, Noncurrent Plan Name [Domain] Plan Name [Domain] Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent Global Intangible Low Taxed Income, Percent Global Intangible Low Taxed Income, Percent Global Intangible Low Taxed Income, Percent Issuance of restricted stock, net of forfeitures Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Document Fiscal Period Focus Document Fiscal Period Focus Investment Advisory Services [Member] Investment Advisory Services [Member] Investment Advisory Services [Member] Total deferred taxes Deferred Income Tax Expense (Benefit) Document Type Document Type State and local income taxes, net of federal income taxes, effective tax rate Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Entity Tax Identification Number Entity Tax Identification Number Entity Address, Postal Zip Code Entity Address, Postal Zip Code Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations Investment Income, Investment Expense Investment Income, Investment Expense Income Statement [Abstract] Income Statement [Abstract] Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation [Domain] Other comprehensive income (loss) Other comprehensive income Other Comprehensive Income (Loss), Net of Tax Lessee, Operating Leases Lessee, Operating Leases [Text Block] Schedule Of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Current taxes: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Litigation Settlement, Expense Litigation Settlement, Expense Effective Income Tax Rate Reconciliation, Percent Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Finite-Lived Intangible Assets Disposed [Line Items] Finite-Lived Intangible Assets Disposed [Line Items] [Line Items] for Finite-Lived Intangible Assets Disposed [Table] Cash paid during the year for income taxes Income Taxes Paid, Net Total expenses Costs and Expenses Amortization of intangible assets Amortization expense Amortization of Intangible Assets Changes in goodwill Goodwill [Roll Forward] Entity Interactive Data Current Entity Interactive Data Current Canadian rate differential, effective tax rate Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Use of Estimates Use of Estimates, Policy [Policy Text Block] Provision for income taxes Income tax expense (benefit) Income Tax Expense (Benefit) Net intersegment revenues Net Intersegment Revenues Net intersegment revenues. Adjusted pre-tax income Share Pretax Income Goal Share pretax income goal. Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Total current assets Assets, Current Lessee, Operating Lease, Liability, Maturity Lessee, Operating Lease, Liability, Maturity [Table Text Block] Excess tax benefits from stock-based compensation Excess Tax Benefit from Share-based Compensation, Operating Activities INVESTMENTS Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Property and Equipment, Net by Geographic Area Long-lived Assets by Geographic Areas [Table Text Block] 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four Acquisition of Woodway, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Total current liabilities Liabilities, Current Accounting Changes and Error Corrections [Abstract] Accounting Changes and Error Corrections [Abstract] Accounting Standards Update 2016-09 [Member] Accounting Standards Update 2016-09 [Member] General and administrative General and Administrative Expense Property, Plant and Equipment, Type Property, Plant and Equipment, Type [Domain] REGULATORY CAPITAL REQUIREMENTS Regulatory Capital Requirements under Banking Regulations [Text Block] Local Phone Number Local Phone Number Investments, at fair value Short-term Investments Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Schedule Of Investments [Line Items] Schedule of Investments [Line Items] Related Party Related Party [Axis] Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Total liabilities and stockholders’ equity Liabilities and Equity 2020 Operating Leases, Future Minimum Payments, Due in Two Years Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Accounts receivable Accounts Receivable, after Allowance for Credit Loss, Current Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] DESCRIPTION OF THE BUSINESS Nature of Operations [Text Block] Dividends payable Dividends Payable, Current Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Equity Components [Axis] Equity Components [Axis] Estimated Litigation Liability, Current Estimated Litigation Liability, Current Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Estimated amortization expense for intangible assets for the next five years Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Canada Income (Loss) from Continuing Operations before Income Taxes, Foreign Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Stock Issued During Period, Value, Restricted Stock Award, Gross Stock Issued During Period, Value, Restricted Stock Award, Gross Award Type [Axis] Award Type [Axis] Earnings per share: Earnings Per Share, Basic and Diluted [Abstract] Operating Segments Operating Segments [Member] Canadian Plan restricted stock expense Canadian Plan Restricted Stock Expense [Member] Canadian plan restricted stock expense. U.S. Federal corporate tax rate Income tax provision computed at US federal statutory rate, effective tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 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] Other revenue Other revenue Other revenue Diluted (in shares) Weighted average shares outstanding – diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Westwood Hospitality Fund I LLC [Member] Westwood Hospitality Fund I LLC [Member] Westwood Hospitality Fund I LLC [Member] Intangibles Deferred Tax Liabilities, Intangible Assets Eliminations Intersegment Eliminations [Member] Compensation and benefits payable Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Property and equipment Deferred Tax Liabilities, Property, Plant and Equipment Common stock, shares issued Common Stock, Shares, Issued Noncash Tenant Improvements Noncash Tenant Improvements Noncash Tenant Improvements Operating Lease, Right-of-Use Asset Operating Lease, Right-of-Use Asset Fee revenues from Westwood VIEs Variable Interest Entity, Measure of Activity, Revenues Finite-Lived Intangible Assets Sold, Gross Finite-Lived Intangible Assets Sold, Gross Finite-Lived Intangible Assets Sold, Gross Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Purchases of property, equipment and other Payments to Acquire Productive Assets Restricted shares subject only to a service condition: Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Other current assets Increase (Decrease) in Other Current Assets Subsequent Events [Abstract] Subsequent Events [Abstract] Westwood mutual funds Mutual Fund Administration And Distribution Expenses related to the administration, distribution and marketing of mutual funds. Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Axis] Investment Balances Debt Securities, Trading, and Equity Securities, FV-NI [Table Text Block] Percentage of deferred share units vesting Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Concentration Risk [Table] Concentration Risk [Table] Total current taxes Current Income Tax Expense (Benefit) Adjustments to Additional Paid in Capital, Income Tax Deficiency from Share-based Compensation Adjustments to Additional Paid in Capital, Income Tax Deficiency from Share-based Compensation Net income Net income Net Income (Loss) Attributable to Parent Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Common Trust Funds Common Trust Funds [Member] Common trust funds. Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Defined Benefit Plan, Plan Assets, Category [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] EMPLOYEE BENEFITS Compensation and Employee Benefit Plans [Text Block] Other Deferred Tax Assets, Other 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] Cost Trading Securities, Cost Trading Securities, Cost Purchases of treasury stock, shares Purchase of treasury stock, shares Treasury Stock, Shares, Acquired Decrease in income tax provision Significant Change in Income Tax Provision is Reasonably Possible, Amount of Unrecorded Benefit Significant Change in Income Tax Provision is Reasonably Possible, Amount of Unrecorded Benefit Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Entity Small Business Entity Small Business QUARTERLY FINANCIAL DATA (Unaudited) Quarterly Financial Information [Text Block] Entity File Number Entity File Number Number of largest clients Number Of Major Customers Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Customer Concentration Risk Customer Concentration Risk [Member] Schedule Of Available For Sale Securities [Line Items] Debt Securities, Available-for-sale [Line Items] Operating Lease, Liability, Current Operating Lease, Liability, Current COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Contingent consideration Business Combination, Contingent Consideration, Liability Payments to Acquire Intangible Assets Payments to Acquire Intangible Assets Fair value of vested shares Fair value of shares vested (in thousands) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Sublease Income Sublease Income Principles of consolidation Consolidation, Policy [Policy Text Block] 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three Number of vested shares from employees on the date vesting Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Components of Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Share-based Compensation Award, Tranche Two Share-based Payment Arrangement, Tranche Two [Member] Proceeds from Sale of Property, Plant, and Equipment Proceeds from Sale of Property, Plant, and Equipment UCITS Fund [Member] UCITS Fund [Member] UCITS Fund [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Treasury Stock, Value, Acquired, Cost Method Stock Repurchased During Period, Value Private Equity Investment Purchase Private Equity Investment Purchase Private Equity Investment Purchase Employee compensation and benefits Labor and Related Expense Total Expense Recorded for Stock Based Compensation Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Other liabilities Increase (Decrease) in Other Operating Liabilities Restricted shares granted to employees vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Product and Service [Axis] Product and Service [Axis] State and local income taxes, net of federal income taxes Effective Income Tax Rate Reconciliation, Tax Contingency, Domestic, Amount Number of reporting units Number of Reporting Units Global Intangible Low Taxed Income, Net Deductions Global Intangible Low Taxed Income, Net Deductions Global Intangible Low Taxed Income, Net Deductions Investments in trading securities Corporate Investment Debt Securities, Trading, and Equity Securities, FV-NI Proceeds from Divestiture of Businesses Proceeds from Divestiture of Businesses Other current assets Other Assets, Current Dividend income Investment Income, Dividend State and local Current State and Local Tax Expense (Benefit) Variable Interest Entities Variable Interest Entities [Axis] Values of Assets Within Fair Value Hierarchy Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Treasury Stock, Common, Shares Treasury Stock, Common, Shares Income taxes payable Increase (Decrease) in Accrued Taxes Payable Benefit Plans [Member] Benefit Plans [Member] Benefit plans. Current Liabilities: Liabilities, Current [Abstract] Share price Share Price Dividends declared ($2.07 in 2015, $1.82 per share in 2014, $1.64 per share in 2013) Dividends, Common Stock LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Gross Unrealized Losses Trading Securities, Unrealized Holding Loss Trading Securities, Unrealized Holding Loss Cash and stock Business Combination, Consideration Transferred, Cash and Equity Interests Issued and Issuable Business Combination, Consideration Transferred, Cash and Equity Interests Issued and Issuable Non-vested, January 1, 2015 (in dollars per share) Non-vested, December 31, 2015 (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Fund purchases of common stock Fund Purchases Of Common Stock Fund purchases of common stock. Revenue from Contract with Customer, Excluding Assessed Tax Revenue from Contract with Customer, Excluding Assessed Tax Revenue from Contract with Customer, Excluding Assessed Tax Schedule of Investments [Abstract] Schedule of Investments [Abstract] Effective Income Tax Rate Reconciliation, Tax Contingency, Amount Effective Income Tax Rate Reconciliation, Tax Contingency, Amount Money market funds Money Market Funds [Member] Canadian Plan Canadian Plan [Member] Canadian Plan. Other operating expenses Other Cost and Expense, Operating INCOME TAXES Income Tax Disclosure [Text Block] Total assets measured at fair value Fair Value, Net Asset (Liability) Tax Year 2017 [Member] Tax Year 2017 [Member] 2022 Operating Leases, Future Minimum Payments, Due in Four Years Trust Trust for Benefit of Employees [Member] Trust Fee [Member] Trust Fee [Member] Trust Fee [Member] Segment Reporting [Abstract] Segment Reporting [Abstract] Income tax provision computed at US federal statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Asset Management [Member] Asset Management [Member] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Gain on sale of operations Gain on sale of operations Gain on sale of operations Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Long Term Investment, at Cost, in a private investment fund Long Term Investment, at Cost, in a private investment fund Long Term Investment, at Cost, in a private investment fund Significant Accounting Policy [Table] Significant Accounting Policy [Table] Significant accounting policy. Effect of currency rate changes on cash Effect of Exchange Rate on Cash and Cash Equivalents Employee Employee [Member] Employee [Member] U.S. Federal Deferred Federal Income Tax Expense (Benefit) Inputs, Net Asset Value [Member] Inputs, Net Asset Value [Member] Inputs, Net Asset Value [Member] Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Remaining Lease Term Earnings Per Share, Policy [Policy Text Block] Earnings Per Share, Policy [Policy Text Block] Litigation Case Litigation Case [Axis] Related Party Related Party [Domain] Earnings per share: Earnings Per Share [Abstract] Total number of shares that may be issued under the stock based compensation Plan (including predecessor plans to the Plan) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Revenue Recognition, Policy [Policy Text Block] Revenue [Policy Text Block] Leases [Abstract] Stock Repurchase Program, Number of Shares Authorized to be Repurchased Stock Repurchase Program, Number of Shares Authorized to be Repurchased Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Restricted Shares Subject to Service and Performance Conditions Restricted Shares Subject to Service and Performance Conditions Restricted Shares Subject To Service And Performance Conditions [Member] Restricted shares subject to service and performance conditions. Subsequent Event [Line Items] Subsequent Event [Line Items] Investments in securities: Investments, Fair Value Disclosure [Abstract] Minimum [Member] Minimum [Member] Revenue accounted by major clients Concentration Risk, Percentage Purchases of treasury stock Treasury Stock, Value, Acquired, Cost Method Security Exchange Name Security Exchange Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Address, Address Line Two Entity Address, Address Line Two Entity Address, Address Line One Entity Address, Address Line One Current Assets: Assets, Current [Abstract] Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Liability for Uncertainty in Income Taxes, Current Liability for Uncertainty in Income Taxes, Current Uncertain tax position Balance at January 1, 2017 Balance at December 31, 2017 Unrecognized Tax Benefits Operating Lease, Cost Operating Lease, Cost Accrued dividends Dividends Payable Non Current Dividends payable non current. Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities, Current Accounts Payable and Accrued Liabilities, Current Service condition restricted stock expense Stock Based Compensation Expense Subject To Service Condition [Member] Stock based compensation expense subject to service condition. Deferred Compensation Share Based Payments Deferred Compensation, Share-based Payments [Member] Finite Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Amount at Risk Risk Of Loss The risk of loss on Investment in VIE. Noncompete Agreements [Member] Noncompete Agreements [Member] Total revenues Total revenues Revenues Fees earned from related party Revenue from Related Parties Other Liabilities, Noncurrent Other Liabilities, Noncurrent Share Based Compensation Award Tranche Four Share Based Compensation Award Tranche Four [Member] Share based compensation award tranche four. Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase for Purchase Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase for Purchase Litigation claim for damages Loss Contingency, Damages Sought, Value Dividends declared, per share Dividends Payable, Amount Per Share EARNINGS PER SHARE Earnings Per Share [Text Block] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Payments for Other Fees Payments for Other Fees Trade Names [Member] Trade Names [Member] Unrealized (gains) losses on investments Unrealized gains/(losses) Trading Securities, Change in Unrealized Holding Gain (Loss) Schedule Of Investments [Table] Schedule of Investments [Table] Disposal Group Name [Axis] Disposal Group Name [Axis] Supplemental cash flow information: Supplemental Cash Flow Elements [Abstract] Westwood International Advisors Inc Westwood International Advisors Inc [Member] Westwood International Advisors Inc. Computation of Basic and Diluted Shares Earnings Per Share Reconciliation [Abstract] Business Combinations Business Combinations Policy [Policy Text Block] Issuance of restricted stock, net of forfeitures, shares Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Remaining unrecognized compensation cost Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Summary of intangible assets Intangible Assets, Net (Excluding Goodwill) [Abstract] Document And Entity Information [Abstract] Document And Entity Information [Abstract] Document and entity information. Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Maximum [Member] Maximum [Member] Income Tax Provision (Benefit) as Set Forth in the Consolidated Statements of Income Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Title of 12(b) Security Title of 12(b) Security