2103100 - Disclosure - ACQUISITIONS AND DIVESTITURES link:presentationLink link:calculationLink link:definitionLink 2403403 - Disclosure - ACQUISITIONS AND DIVESTITURES - Assets and Liabilities Disposed Of (Details) link:presentationLink link:calculationLink link:definitionLink 2403402 - Disclosure - ACQUISITIONS AND DIVESTITURES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2303301 - Disclosure - ACQUISITIONS AND DIVESTITURES (Tables) link:presentationLink link:calculationLink link:definitionLink 2111100 - Disclosure - BENEFITS PAYABLE link:presentationLink link:calculationLink link:definitionLink 2411402 - Disclosure - BENEFITS PAYABLE - Activity in Benefits Payable (Details) link:presentationLink link:calculationLink link:definitionLink 2411403 - Disclosure - BENEFITS PAYABLE - Favorable Medical Claims Reserve Development (Details) link:presentationLink link:calculationLink link:definitionLink 2411405 - Disclosure - BENEFITS PAYABLE - Incurred and Paid Claims Development (Details) link:presentationLink link:calculationLink link:definitionLink 2411404 - Disclosure - BENEFITS PAYABLE - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2411406 - Disclosure - BENEFITS PAYABLE - Reconciliation to Consolidated (Details) link:presentationLink link:calculationLink link:definitionLink 2311301 - Disclosure - BENEFITS PAYABLE (Tables) link:presentationLink link:calculationLink link:definitionLink 2117100 - Disclosure - COMMITMENTS, GUARANTEES AND CONTINGENCIES link:presentationLink link:calculationLink link:definitionLink 2417401 - Disclosure - COMMITMENTS, GUARANTEES AND CONTINGENCIES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 1001000 - Statement - Consolidated Balance Sheets link:presentationLink link:calculationLink link:definitionLink 1001501 - Statement - Consolidated Balance Sheets (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 1005000 - Statement - Consolidated Statements of Cash Flows link:presentationLink link:calculationLink link:definitionLink 1003000 - Statement - Consolidated Statements of Comprehensive Income link:presentationLink link:calculationLink link:definitionLink 1002000 - Statement - Consolidated Statements of Income link:presentationLink link:calculationLink link:definitionLink 1004000 - Statement - Consolidated Statements of Stockholders' Equity link:presentationLink link:calculationLink link:definitionLink 0001000 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 2113100 - Disclosure - DEBT link:presentationLink link:calculationLink link:definitionLink 2413406 - Disclosure - DEBT - Commercial Paper (Details) link:presentationLink link:calculationLink link:definitionLink 2413405 - Disclosure - DEBT - Credit Agreement (Details) link:presentationLink link:calculationLink link:definitionLink 2413402 - Disclosure - DEBT - Debt Outstanding (Details) link:presentationLink link:calculationLink link:definitionLink 2413403 - Disclosure - DEBT - Maturities of Debt (Details) link:presentationLink link:calculationLink link:definitionLink 2413404 - Disclosure - DEBT - Senior Notes (Details) link:presentationLink link:calculationLink link:definitionLink 2313301 - Disclosure - DEBT (Tables) link:presentationLink link:calculationLink link:definitionLink 2413407 - Disclosure - DEBT - Term Note (Details) link:presentationLink link:calculationLink link:definitionLink 2115100 - Disclosure - EARNINGS PER COMMON SHARE COMPUTATION link:presentationLink link:calculationLink link:definitionLink 2415402 - Disclosure - EARNINGS PER COMMON SHARE COMPUTATION - Details Supporting Computation of Earnings Per Common Share (Details) link:presentationLink link:calculationLink link:definitionLink 2315301 - Disclosure - EARNINGS PER COMMON SHARE COMPUTATION (Tables) link:presentationLink link:calculationLink link:definitionLink 2114100 - Disclosure - EMPLOYEE BENEFIT PLANS link:presentationLink link:calculationLink link:definitionLink 2414402 - Disclosure - EMPLOYEE BENEFIT PLANS - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2414406 - Disclosure - EMPLOYEE BENEFIT PLANS - Option Plans Activity (Details) link:presentationLink link:calculationLink link:definitionLink 2414404 - Disclosure - EMPLOYEE BENEFIT PLANS - Restricted Stock Activity (Details) link:presentationLink link:calculationLink link:definitionLink 2414403 - Disclosure - EMPLOYEE BENEFIT PLANS - Stock-Based Compensation Expense (Details) link:presentationLink link:calculationLink link:definitionLink 2314301 - Disclosure - EMPLOYEE BENEFIT PLANS (Tables) link:presentationLink link:calculationLink link:definitionLink 2414405 - Disclosure - EMPLOYEE BENEFIT PLANS - Weighted-Average Fair Value Assumptions for Stock Options (Details) link:presentationLink link:calculationLink link:definitionLink 2104100 - Disclosure - EQUITY METHOD INVESTMENT link:presentationLink link:calculationLink link:definitionLink 2404402 - Disclosure - EQUITY METHOD INVESTMENT - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2404403 - Disclosure - EQUITY METHOD INVESTMENT - Summary of Balances Sheets and Income Statement (Details) link:presentationLink link:calculationLink link:definitionLink 2304301 - Disclosure - EQUITY METHOD INVESTMENT (Tables) link:presentationLink link:calculationLink link:definitionLink 2106100 - Disclosure - FAIR VALUE link:presentationLink link:calculationLink link:definitionLink 2406402 - Disclosure - FAIR VALUE - Financial Assets Measured on Recurring Basis (Details) link:presentationLink link:calculationLink link:definitionLink 2406403 - Disclosure - FAIR VALUE - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2406404 - Disclosure - FAIR VALUE - Put and Call Options Measured at Fair Value (Details) link:presentationLink link:calculationLink link:definitionLink 2306301 - Disclosure - FAIR VALUE (Tables) link:presentationLink link:calculationLink link:definitionLink 2109100 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS link:presentationLink link:calculationLink link:definitionLink 2409402 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS - Changes in Carrying Amount of Goodwill by Reportable Segments (Details) link:presentationLink link:calculationLink link:definitionLink 2409403 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS - Details of Intangible Assets Included in Other Long-Term Assets (Details) link:presentationLink link:calculationLink link:definitionLink 2409405 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS - Estimate of Amortization Expense (Details) link:presentationLink link:calculationLink link:definitionLink 2409404 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2309301 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS (Tables) link:presentationLink link:calculationLink link:definitionLink 2112100 - Disclosure - INCOME TAXES link:presentationLink link:calculationLink link:definitionLink 2412404 - Disclosure - INCOME TAXES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2412405 - Disclosure - INCOME TAXES - Principal Components of Net Deferred Tax Balances (Details) link:presentationLink link:calculationLink link:definitionLink 2412402 - Disclosure - INCOME TAXES - Provision for Income Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 2412403 - Disclosure - INCOME TAXES - Provision for Income Taxes Reconciliation (Details) link:presentationLink link:calculationLink link:definitionLink 2312301 - Disclosure - INCOME TAXES (Tables) link:presentationLink link:calculationLink link:definitionLink 2105100 - Disclosure - INVESTMENT SECURITIES link:presentationLink link:calculationLink link:definitionLink 2405406 - Disclosure - INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) link:presentationLink link:calculationLink link:definitionLink 2405403 - Disclosure - INVESTMENT SECURITIES - Gross Unrealized Losses and Fair Values of Securities (Details) link:presentationLink link:calculationLink link:definitionLink 2405402 - Disclosure - INVESTMENT SECURITIES - Investment Securities Classified as Current and Long-Term (Details) link:presentationLink link:calculationLink link:definitionLink 2405404 - Disclosure - INVESTMENT SECURITIES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2405405 - Disclosure - INVESTMENT SECURITIES - Realized Gains (Losses) Included Within Investment Income (Details) link:presentationLink link:calculationLink link:definitionLink 2305301 - Disclosure - INVESTMENT SECURITIES (Tables) link:presentationLink link:calculationLink link:definitionLink 2110100 - Disclosure - LEASES link:presentationLink link:calculationLink link:definitionLink 2410405 - Disclosure - LEASES - Future Annual Minimum Payments Due at Prior Year End (Details) link:presentationLink link:calculationLink link:definitionLink 2410403 - Disclosure - LEASES - Maturity of Lease Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 2410403 - Disclosure - LEASES - Maturity of Lease Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 2410402 - Disclosure - LEASES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2410404 - Disclosure - LEASES - Rent Expense and Sublease Rental Income in Prior Years (Details) link:presentationLink link:calculationLink link:definitionLink 2310301 - Disclosure - LEASES (Tables) link:presentationLink link:calculationLink link:definitionLink 2107100 - Disclosure - MEDICARE PART D link:presentationLink link:calculationLink link:definitionLink 2407402 - Disclosure - MEDICARE PART D (Details) link:presentationLink link:calculationLink link:definitionLink 2307301 - Disclosure - MEDICARE PART D (Tables) link:presentationLink link:calculationLink link:definitionLink 2108100 - Disclosure - PROPERTY AND EQUIPMENT, NET link:presentationLink link:calculationLink link:definitionLink 2408403 - Disclosure - PROPERTY AND EQUIPMENT, NET - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2408402 - Disclosure - PROPERTY AND EQUIPMENT, NET - Schedule of Property and Equipment (Details) link:presentationLink link:calculationLink link:definitionLink 2308301 - Disclosure - PROPERTY AND EQUIPMENT, NET (Tables) link:presentationLink link:calculationLink link:definitionLink 2120100 - Disclosure - QUARTERLY FINANCIAL INFORMATION (Unaudited) link:presentationLink link:calculationLink link:definitionLink 2420402 - Disclosure - QUARTERLY FINANCIAL INFORMATION (Unaudited) (Details) link:presentationLink link:calculationLink link:definitionLink 2320301 - Disclosure - QUARTERLY FINANCIAL INFORMATION (Unaudited) (Tables) link:presentationLink link:calculationLink link:definitionLink 2119100 - Disclosure - REINSURANCE link:presentationLink link:calculationLink link:definitionLink 2419401 - Disclosure - REINSURANCE - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2101100 - Disclosure - REPORTING ENTITY link:presentationLink link:calculationLink link:definitionLink 2401401 - Disclosure - REPORTING ENTITY (Details) link:presentationLink link:calculationLink link:definitionLink 2121100 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION link:presentationLink link:calculationLink link:definitionLink 2421401 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Balance Sheets) (Details) link:presentationLink link:calculationLink link:definitionLink 2421402 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Balance Sheets Share Data) (Details) link:presentationLink link:calculationLink link:definitionLink 2421405 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Statements of Cash Flows) (Details) link:presentationLink link:calculationLink link:definitionLink 2421404 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Statements of Comprehensive Income) (Details) link:presentationLink link:calculationLink link:definitionLink 2421403 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Statements of Income) (Details) link:presentationLink link:calculationLink link:definitionLink 2421406 - Schedule - SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Notes to Condensed Financial Statements) (Details) link:presentationLink link:calculationLink link:definitionLink 2122100 - Schedule - SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS link:presentationLink link:calculationLink link:definitionLink 2422401 - Schedule - SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) link:presentationLink link:calculationLink link:definitionLink 2118100 - Disclosure - SEGMENT INFORMATION link:presentationLink link:calculationLink link:definitionLink 2418402 - Disclosure - SEGMENT INFORMATION - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2418403 - Disclosure - SEGMENT INFORMATION - Segment Results (Details) link:presentationLink link:calculationLink link:definitionLink 2318301 - Disclosure - SEGMENT INFORMATION (Tables) link:presentationLink link:calculationLink link:definitionLink 2116100 - Disclosure - STOCKHOLDERS' EQUITY link:presentationLink link:calculationLink link:definitionLink 2416402 - Disclosure - STOCKHOLDERS' EQUITY - Dividend Payments (Details) link:presentationLink link:calculationLink link:definitionLink 2416403 - Disclosure - STOCKHOLDERS' EQUITY - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2416404 - Disclosure - STOCKHOLDERS' EQUITY - Share Repurchases (Details) link:presentationLink link:calculationLink link:definitionLink 2316301 - Disclosure - STOCKHOLDERS' EQUITY (Tables) link:presentationLink link:calculationLink link:definitionLink 2102100 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES link:presentationLink link:calculationLink link:definitionLink 2402404 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill (Details) link:presentationLink link:calculationLink link:definitionLink 2402402 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 2202201 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies) link:presentationLink link:calculationLink link:definitionLink 2402403 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Workforce Optimization (Details) link:presentationLink link:calculationLink link:definitionLink