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Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Information technology Communications and Information Technology Entity File Number Entity File Number Stock Repurchased During Period, Value Stock Repurchased During Period, Value Schedule Of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] 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] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Product and Service [Axis] Product and Service [Axis] Long-Lived Tangible Asset [Domain] Long-Lived Tangible Asset [Domain] CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Westwood Funds® Westwood Funds [Member] Westwood funds. Entity Small Business Entity Small Business Remaining unrecognized compensation cost Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Trust Trust [Member] Trust. Equity Component Equity Component [Domain] 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. 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Gross Unrealized Gains Debt Securities, Trading, and Equity Securities, Unrealized Gain Debt Securities, Trading, and Equity Securities, Unrealized Gain Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Investment Income, Investment Expense Investment Income, Investment Expense Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Investing Activities Disaggregation of Revenue [Abstract] Disaggregation of Revenue [Abstract] Change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Property and equipment, accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Vested (dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Total current liabilities Liabilities, Current Restricted stock returned for payment of taxes Payment, Tax Withholding, Share-based Payment Arrangement Eliminations Intersegment Eliminations [Member] Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Tax Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Tax Unrealized Gains (Losses) on Private Investments Unrealized Gains (Losses) on Private Investments Unrealized Gains (Losses) on Private Investments Money market funds Money Market Funds [Member] Revenue from Contract with Customer, Including Assessed Tax Revenue from Contract with Customer, Including Assessed Tax Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Asia [Member] Asia [Member] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Investment Performance [Member] Investment Performance [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] stock repurchase program stock repurchase program stock repurchase program - authorization increase subsequent to financial statement date Fee revenues from Westwood VIEs Variable Interest Entity, Measure of Activity, Revenues Title of 12(b) Security Title of 12(b) Security Mutual Fund [Member] Mutual Fund [Member] Statement [Table] Statement [Table] Other current assets Other Assets, Current Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Statistical Measurement [Axis] Statistical Measurement [Axis] Payment for Repurchases of Stock for Benefit Plan Payment for Repurchases of Stock for Benefit Plan Payment for Repurchases of Stock for Benefit Plan Adjustments to Additional Paid in Capital, Other Adjustments to Additional Paid in Capital, Other Subsequent Event [Member] Subsequent Event [Member] Investment Advisory Services [Member] Investment Advisory Services [Member] Investment Advisory Services [Member] Intangible assets, net Finite-Lived Intangible Assets, Net Goodwill Goodwill Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Subsequent Event, Description Subsequent Event, Description Gross Unrealized Losses Debt Securities, Trading, and Equity Securities, Unrealized Loss Debt Securities, Trading, and Equity Securities, Unrealized Loss Income taxes payable Accrued Income Taxes, Current Investments Measured at NAV Fair Value Measured at Net Asset Value Per Share [Member] DESCRIPTION OF THE BUSINESS Nature of Operations [Text Block] Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Scenario [Domain] Scenario [Domain] Unobservable input -book value multiple - maximum Unobservable input -book value multiple - maximum Unobservable input -book value multiple - maximum Subsequent Event Type [Axis] Subsequent Event Type [Axis] Geographic Distribution [Axis] Geographic Distribution [Axis] RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Deferred income taxes Deferred Income Tax Expense (Benefit)