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Statement - Condensed Consolidated Statements of Cash Flows (Unaudited) cash, cash equivalent and restricted cash reconciliation link:presentationLink link:calculationLink link:definitionLink 0000009 - Disclosure - Organization and Description of the Company link:presentationLink link:calculationLink link:definitionLink 0000010 - Disclosure - Summary of Significant Accounting Policies link:presentationLink link:calculationLink link:definitionLink 0000011 - Disclosure - Revenue link:presentationLink link:calculationLink link:definitionLink 0000012 - Disclosure - Acquisitions link:presentationLink link:calculationLink link:definitionLink 0000013 - Disclosure - Fair Value Measurements link:presentationLink link:calculationLink link:definitionLink 0000014 - Disclosure - Investment Securities link:presentationLink link:calculationLink link:definitionLink 0000015 - Disclosure - Goodwill and Other Intangible Assets link:presentationLink link:calculationLink link:definitionLink 0000016 - Disclosure - 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Disclosure - Summary of Significant Accounting Policies (Policies) link:presentationLink link:calculationLink link:definitionLink 9954472 - Disclosure - Revenue (Tables) link:presentationLink link:calculationLink link:definitionLink 9954473 - Disclosure - Fair Value Measurements (Tables) link:presentationLink link:calculationLink link:definitionLink 9954474 - Disclosure - Investment Securities (Tables) link:presentationLink link:calculationLink link:definitionLink 9954475 - Disclosure - Goodwill and Other Intangible Assets (Tables) link:presentationLink link:calculationLink link:definitionLink 9954476 - Disclosure - Other Assert and Other Liabilities (Tables) link:presentationLink link:calculationLink link:definitionLink 9954477 - Disclosure - Corporate Debt and Other Borrowings, Net (Tables) link:presentationLink link:calculationLink link:definitionLink 9954478 - Disclosure - Commitment and Contingencies (Tables) link:presentationLink link:calculationLink link:definitionLink 9954479 - 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Revenue - Commission Revenue Disaggregated by Product Category and Timing of Transfer of Good or Service (Details) link:presentationLink link:calculationLink link:definitionLink 9954487 - Disclosure - Revenue - Transaction and Fee Revenue Disaggregated by Timing of Transfer of Good or Service (Details) link:presentationLink link:calculationLink link:definitionLink 9954488 - Disclosure - Revenue - Unearned Revenue Recognized (Details) link:presentationLink link:calculationLink link:definitionLink 9954489 - Disclosure - Acquisitions (Details) link:presentationLink link:calculationLink link:definitionLink 9954490 - Disclosure - Fair Value Measurements - Fair Value Disclosure, Measurement of Contingent Consideration Using Monte-Carlo Simulation Model (Details) link:presentationLink link:calculationLink link:definitionLink 9954491 - Disclosure - Fair Value Measurements - Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) link:presentationLink link:calculationLink link:definitionLink 9954492 - Disclosure - Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring and Nonrecurring Basis (Details) link:presentationLink link:calculationLink link:definitionLink 9954493 - Disclosure - Fair Value Measurements - Not Measured at Fair Value (Details) link:presentationLink link:calculationLink link:definitionLink 9954494 - Disclosure - Investment Securities - Summary (Details) link:presentationLink link:calculationLink link:definitionLink 9954495 - Disclosure - Investment Securities (Details 1) link:presentationLink link:calculationLink link:definitionLink 9954496 - Disclosure - Goodwill and Other Intangible Assets - Goodwill (Details) link:presentationLink link:calculationLink link:definitionLink 9954497 - Disclosure - Goodwill and Other Intangible Assets - Intangible Assets (Components) (Details) link:presentationLink link:calculationLink link:definitionLink 9954498 - Disclosure - Goodwill and Other Intangible Assets (Future Amortization Expense) (Details) link:presentationLink link:calculationLink link:definitionLink 9954499 - Disclosure - Other Assert and Other Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9954500 - Disclosure - Corporate Debt and Other Borrowings, Net (Long-Term Borrowings Outstanding) (Details) link:presentationLink link:calculationLink link:definitionLink 9954501 - Disclosure - Corporate Debt and Other Borrowings, Net (Other Borrowings Outstanding) (Details) link:presentationLink link:calculationLink link:definitionLink 9954502 - Disclosure - Corporate Debt and Other Borrowings, Net - Textuals (Details) link:presentationLink link:calculationLink link:definitionLink 9954503 - Disclosure - Commitments and Contingencies (Legal) (Details) link:presentationLink link:calculationLink link:definitionLink 9954504 - Disclosure - Commitments and Contingencies (Other Commitments) (Details) link:presentationLink link:calculationLink link:definitionLink 9954505 - Disclosure - Commitments and Contingencies - Self insurance Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9954506 - Disclosure - Stockholders' Equity (Dividends Paid) (Details) link:presentationLink link:calculationLink link:definitionLink 9954507 - Disclosure - Stockholdes' Equity (Share Repurchases) (Details) link:presentationLink link:calculationLink link:definitionLink 9954508 - Disclosure - Share-Based Compensation (Texuals) (Details) link:presentationLink link:calculationLink link:definitionLink 9954509 - Disclosure - Share-Based Compensation - Stock Option and Warrant Activity (Details) link:presentationLink link:calculationLink link:definitionLink 9954510 - Disclosure - Share-Based Compensation - Outstanding Stock Options and Warrant Information (Details) link:presentationLink link:calculationLink link:definitionLink 9954511 - Disclosure - Share-Based Compensation - Restricted Stock Activity (Details) link:presentationLink link:calculationLink link:definitionLink 9954512 - Disclosure - Earnings per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9954513 - Disclosure - 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