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Outstanding at beginning of period (in dollars per share) Outstanding at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Fixed maturities, amortized cost, noncurrent Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent Net payments attributable to: Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Due in one year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One CarelonRx CarelonRx Segment [Member] CarelonRx Segment [Member] Schedule of Denominator for Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt: Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Segment Information Segment Reporting [Text Block] Investments Investment in Debt and Equity Securities and Other Trading Assets [Text Block] Maturities, calls and redemptions from investments Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Minimum Minimum [Member] Investment Type [Axis] Investment Type [Axis] Expiration Date Trading Arrangement Expiration Date Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Derivative Instruments, Gain (Loss) by Hedging Relationship [Axis] Hedging Relationship [Axis] Derivatives - other liabilities Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement Liabilities Liabilities [Abstract] Effect of foreign exchange rates on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Non-Rule 10b5-1 Arrangement 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Disclosure Loss Contingency, Estimate of Possible Loss Loss Contingency, Estimate of Possible Loss Dividends and dividend equivalents Dividends, Common Stock Exercisable at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Gross losses Gross Losses From Other Investments Gross Losses From Other Investments Common stock, shares authorized (in shares) Common Stock, Shares Authorized Other policyholder liabilities Other Policyholder Funds Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Fixed maturities, allowance for credit Loss, noncurrent Debt Securities, Available-for-Sale, Allowance for Credit Loss, Noncurrent Exercisable at end of period, Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value Gross realized gains from sales Debt Securities, Available-for-Sale, Realized Gain Due after ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Exercise Price Award Exercise Price Schedule of Operating Model Transformation Initiatives and Related Costs [Table] Restructuring Cost [Table] Investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Litigation Status [Axis] Litigation Status [Axis] Fair Value, Recurring Fair Value, Recurring [Member] Segment Reporting [Line Items] Segment Reporting [Line Items] Fair Value, Separate Account Investment [Table] Fair Value, Separate Account Investment [Table] Document Quarterly Report Document Quarterly Report Extension period Long-Term Purchase Commitment, Period Repurchase Agreements and 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Adjustment Expense, Claims Paid, Prior Years Repayments of long-term borrowings Repayments of Long-Term Debt Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Equity method investments Equity Method Investments Liability for employee termination costs Restructuring Reserve Common equity securities Common Equity Securities [Member] Common Equity Securities [Member] Equity Component [Domain] Equity Component [Domain] Fixed maturities, amortized cost, current Debt Securities, Available-for-Sale, Amortized Cost, Current Income Tax Receivable Net Income Tax Receivable Net Income Tax Receivable Net PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Expenses Benefits, Losses and Expenses [Abstract] Adoption Date Trading Arrangement Adoption Date Debt instrument interest rate Debt Instrument, Interest Rate, Stated Percentage Premium receivable, allowance for doubtful accounts Premium Receivable, Allowance for 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Restricted stock awards granted during the period (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 Change in gross unrealized investment gains (losses) OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax Net losses on equity securities Equity Securities, FV-NI, Gain (Loss) Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Subsequent Event Type [Domain] Subsequent Event Type [Domain] Retained Earnings Retained Earnings [Member] Changes in securities lending collateral Increase (Decrease) in Collateral Held under Securities Lending Revolving Credit Facility Revolving Credit Facility [Member] 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 Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Total change in unrealized investment gains (losses), net of tax OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Corporate securities Corporate Debt Securities [Member] Diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Schedule of Reconciliation of Net Incurred Medical Claims to Benefit Expense Reconciliation of Net Incurred Medical Claims to Benefit Expense [Table Text Block] Tabular Disclosure For Reconciliation of Net Incurred Medical Claims to Benefit Expense. Cash Flow Hedging Cash Flow Hedging [Member] Litigation Case [Domain] Litigation Case [Domain] Amortization of other intangible assets Intangible Asset, Finite-Lived, Amortization Expense Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Reclassification from AOCI, current period, tax Reclassification from AOCI, Current Period, Tax Product and service revenue Revenue from Contract with Customer, Excluding Assessed Tax Property and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Commercial paper Line of Credit, Current Financial Instruments [Domain] Major Types of Fixed Maturity Securities [Domain] Financial Instruments [Domain] Issuance of common stock under employee stock plans, net of related tax benefits Stock Issued During Period, Value, Stock Options Exercised Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Estimate of Fair Value Measurement Estimate of Fair Value Measurement [Member] Other, net Payment for (Proceeds from) Other Investing Activity Other Comprehensive Income (Loss), Other, Before Tax Other Comprehensive Income (Loss), Other, Before Tax Other Comprehensive Income (Loss), Other, Before Tax Investment [Table] Schedule of Gain (Loss) on Securities [Table] Percentage of total assets at fair value Percentage of Total Assets Presented at Fair Value Percentage of Total Assets Presented at Fair Value Recovery of accounts receivable related to prior year Accounts Receivable, Allowance for Credit Loss, Recovery, Prior Years Accounts Receivable, Allowance for Credit Loss, Recovery, Prior Years Segment Reporting [Table] Segment Reporting [Table] Stock Options, Additional Disclosures Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract] Cash Cash [Member] Schedule of Current and Long-Term Investments, Available-For-Sale Schedule of Available-for-Sale Securities Reconciliation [Table Text Block] Other current assets Other Assets, Current Recognized gain on hedging derivatives Derivative, Gain on Derivative Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Estimated fair value, less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Operating gain (loss) Reportable segments’ operating gain Operating Income (Loss) Schedule of Cash Dividend Activity Dividends Declared [Table Text Block] Current Fiscal Year End Date Current Fiscal Year End Date Corporate & Other Corporate & Other Segment [Member] Corporate & Other Segment Gain (loss) on sale of business Gain on sale of business Gain (loss) on sale of business Gain (Loss) on Disposition of Business Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Derivative [Line Items] Derivative [Line Items] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Operating revenue - unaffiliated Unaffiliated [Member] Unaffiliated [Member] Securities lending transactions, initial collateral percentage value Securities Lending Transactions Initial Collateral Percentage Value Initial minimum percentage of cash and/or securities collateral accepted as compared to the value of securities on loan in a securities lending transaction. Dividends per share (in dollars per share) Dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Schedule of Amortized Cost and Fair Value of Fixed Maturity Securities, By Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Equity securities: Equity Securities [Member] Schedule of Reconciliation of Medical Claims Payable Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Schedule of Stock Option Activity Share-Based Payment Arrangement, Option, Activity [Table Text Block] Weighted- Average Option Price per Share Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Impairment of property and equipment Asset, Impairment Loss Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Net gains (losses): Debt Securities, Available-for-Sale, Realized Gain (Loss) [Abstract] Common stock, shares issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] 2026-2027 Operating Model Transformation 2026-2027 Operating Model Transformation [Member] 2026-2027 Operating Model Transformation Premiums Premiums Earned, Net Allowance For Credit Losses Allowance for credit losses Debt Securities, Available-for-Sale, Allowance for Credit Loss Gross unrealized loss, 12 months or greater Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Fixed maturity securities (amortized cost of $25,962 and $25,773; allowance for credit losses of $55 and $21) Debt Securities, Available-for-Sale, Current Statement, Equity Components [Axis] Equity Components [Axis] Product and Service [Domain] Product and Service [Domain] Entity Interactive Data Current Entity Interactive Data Current Net loss (gain) attributable to noncontrolling interests Net loss (gain) attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Deferred tax liabilities, net Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Estimated Fair Value Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract] Accounts payable and accrued expenses Accounts Payable and Accrued Liabilities, Current Entity Small Business Entity Small Business Total shareholders’ comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Unearned income Unearned Premiums Termination Date Trading Arrangement Termination Date 2026 Short-Duration Insurance Contract, Accident Year 2026 [Member] Number of putative nationwide classes of plaintiffs Number of Plaintiffs Number of Plaintiffs Changes in bank overdrafts Increase (Decrease) in Outstanding Checks, Financing Activities Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Recognized loss on hedging derivatives Derivative, Loss on Derivative Other Comprehensive Income (Loss), Other, Tax Effect Other Comprehensive Income (Loss), Other, Tax Effect Other Comprehensive Income (Loss), Other, Tax Effect Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Change in pension and other benefits Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Current period Current Year Claims and Claims Adjustment Expense Other current liabilities Other Liabilities, Current Government sponsored securities US Government-sponsored Enterprises Debt Securities [Member] Other noncurrent assets Other Assets, Noncurrent Document Type Document Type Debt instruments, repurchased face amount Debt Instrument, Repurchased Face Amount Purchases of subsidiaries, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired 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 as of Grant Date Award Grant Date Fair Value Schedule of Estimated Fair Value by Level Carrying And Fair Values By Level Of Financial Instruments Not Recorded At Fair Value On Consolidated Balance Sheet [Table Text Block] -- None. No documentation exists for this element. -- Schedule of Aggregate Fair Value and Gross Unrealized Loss of Fixed Maturity Securities in an Unrealized Loss Position Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Authorization remaining at the end of the period Share Repurchase Program, Remaining Authorized, Amount Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Proceeds from long-term borrowings Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number Consolidation Items [Axis] Consolidation Items [Axis] Equity securities: Available-for-Sale Securities, Equity Securities [Abstract] Available-for-Sale Securities, Equity Securities Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Gross unrealized loss, less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Income before income tax expense Income before income tax expense Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Commitments and contingencies – Note 10 Commitments and Contingencies Cash and cash equivalents Restricted Cash and Investments, Current Proceeds from sale of investments Proceeds from sale of equity and fixed maturity securities Proceeds from sale of equity and fixed maturity securities. Total revenues Revenues Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Equity in net earnings of other invested assets Income (Loss) from Equity Method Investments Investment [Line Items] Gain (Loss) on Securities [Line Items] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Award vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Net incurred but not reported liabilities plus expected development on reported claims Short-Duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net Ceded medical claims payable, end of period Liability for Claims and Claims Adjustment Expense, Ceded Medical Claims Payable Liability for Claims and Claims Adjustment Expense, Ceded Medical Claims Payable Liabilities and equity Liabilities and Equity [Abstract] Impairment losses recognized in income Impairment (losses) reversals on investments Total impairment (losses) reversals on investments, before considering whether or not such amount is recognized in earnings or other comprehensive income. Exercisable at end of period, Weighted-Average Remaining Contractual Life Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term Self-funded receivables, allowance for doubtful accounts Self-funded Receivables, Allowance For Doubtful Accounts The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross self-funded receivable to net realizable value. Schedule of Fair Value Measurements by Level Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Award Type [Domain] Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Fair Value Fair Value Disclosures [Text Block] Level III Fair Value, Inputs, Level 3 [Member] United States Government securities United States Government securities US Government Agencies Debt Securities [Member] Weighted-average expected life (years) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term PEO Name PEO Name Total net payments Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid 2024 Short-Duration Insurance Contract, Accident Year 2024 [Member] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Legal Entity [Axis] Legal Entity [Axis] Notes Notes Payable Fixed maturity securities (amortized cost of $1,263 and $1,116; allowance for credit losses of $$0 and $0) Debt Securities, Available-for-Sale, Noncurrent Liberty Dental Liberty Dental [Member] Liberty Dental Payments for restructuring Payments for Restructuring Exercised (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Revenue Recognition Revenue [Policy Text Block] Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Debt Instrument [Axis] Debt Instrument [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Overnight and Continuous Maturity Overnight [Member] Ownership percentage Equity Method Investment, Ownership Percentage Share-based compensation Share-Based Payment Arrangement, Noncash Expense Foreign government securities Foreign Government Debt [Member] Carrying Value Of Outstanding Borrowings Schedule of Debt [Table Text Block] Reportable Segments Reportable Segments [Member] Reportable Segments Customer [Domain] Customer [Domain] Investment, Name [Domain] Investment, Name [Domain] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Due after five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Basic (in dollars per share) Earnings Per Share, Basic Net losses on investments Investment Gains (Losses) Investment Gains (Losses) Repurchase and retirement of common stock Payments for Repurchase of Common Stock Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] CMS Notice of Possible Sanction CMS Notice of Possible Sanction [Member] CMS Notice of Possible Sanction Long-term debt, less current portion Long-Term Debt, Excluding Current Maturities Award Type [Axis] Award Type [Axis] 4.900% Senior Unsecured Notes Due 2026 4.900% Senior Unsecured Notes Due 2026 [Member] 4.900% Senior Unsecured Notes Due 2026 Other realized losses recognized in income Other Realized Losses Recognized in Income Other Realized Losses Recognized in Income Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Surplus Notes Surplus Notes [Member] Surplus Notes [Member] Schedule of Share Repurchases Class of Treasury Stock [Table Text Block] Net losses on financial instruments Net losses on financial instruments Net losses on financial instruments Net (Losses) Gains on Financial Instruments Net (Losses) Gains on Financial Instruments Retained earnings Retained Earnings (Accumulated Deficit) Restructuring and Related Activities [Abstract] Products and Services Product and Service [Axis] Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Investment Holdings [Table] Investment Holdings [Table] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Estimated Fair Value Total fixed maturity securities Fixed maturity securities, available-for-sale: Debt Securities, Available-for-Sale Volatility factor Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Fair Value Measurement [Domain] Fair Value Measurement [Domain] Carelon Services Carelon Services Segment [Member] Carelon Services Segment Employee Termination Employee Severance [Member] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] Insurance [Abstract] Insurance [Abstract] Quarterly dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Receivables Receivable [Policy Text Block] Equity Awards Adjustments Equity Awards Adjustments [Member] Hedging Relationship [Domain] Hedging Relationship [Domain] Net realized losses from sales of fixed maturity securities Debt Securities, Available-for-Sale, Realized Gain (Loss) Total liabilities and equity Liabilities and Equity Employee Stock Option Share-Based Payment Arrangement, Option [Member] Noncontrolling interests Equity, Attributable to Noncontrolling Interest Life Insurance, Corporate or Bank Owned, Amount Life Insurance, Corporate or Bank Owned, Amount Gross gains Gains From Other Investments Gains From Other Investments Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Related Party [Domain] Related and Nonrelated Parties [Domain] Restructuring Charges Restructuring Charges Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Ceded medical claims payable, beginning of period Ceded medical claims payable, end of period Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Short-term borrowings from the FHLB Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Rolling 12 Months Medical Claims Payable Liability for Future Policy Benefits and Unpaid Claims Disclosure [Text Block] Other asset-backed securities Other Debt Obligations [Member] Income taxes receivable, current Income Taxes Receivable, Current Name Awards Close in Time to MNPI Disclosures, Individual Name 2.375% Senior Unsecured Notes Due 2025 2.375% Senior Unsecured Notes Due 2025 [Member] 2.375% Senior Unsecured Notes Due 2025 Purchases of investments Payments to Acquire Investments Changes in securities lending payable Increase (Decrease) in Securities Lending Payable Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Outstanding at end of period, Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Service fees Service Fees [Member] Service Fees 1.500% Senior Unsecured Notes Due 2026 1.500% Senior Unsecured Notes Due 2026 [Member] 1.500% Senior Unsecured Notes Due 2026 Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, without par value, shares authorized 100,000,000; shares issued and outstanding – none Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Commercial mortgage-backed securities Commercial Mortgage-Backed Securities [Member] Operating Model Transformation [Line Items] Restructuring Cost and Reserve [Line Items] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] AOCI, Other Components [Member] AOCI, Other Components [Member] AOCI, Other Components Credit Facility [Axis] Credit Facility [Axis] Operating Model Transformation Restructuring and Related Activities Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total assets Assets, Fair Value Disclosure Investments Investment, Policy [Policy Text Block] Other investments: Available-for-Sale Securities, Other Investments [Abstract] Available-for-Sale Securities, Other Investments Name Measure Name Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Income Taxes Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Number of securities, less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions Debt Instrument [Line Items] Debt Instrument [Line Items] Net losses on other investments Gain (Loss) on Sale of Other Investments Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Corporate & Other Corporate Segment and Other Operating Segment [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Net put option fair value Business Combination, Contingency Recognized at Acquisition Date, Liability Assumed, Fair Value Repayments of short-term borrowings Repayments of Short-Term Debt Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures Company Selected Measure Amount Company Selected Measure Amount Schedule of Reconciliation of Income Before Income Tax Expense to Reportable Segments Operating Gain Included in the Consolidated Statements of Income Segment Reporting, Reconciliation of Profit (Loss) by Segment to Consolidated [Table Text Block] Unrealized gains recognized on equity securities still held at the end of the period Equity Securities, FV-NI, Unrealized Gain (Loss) Schedule of Investment Gains (Losses) Gain (Loss) on Securities [Table Text Block] Issuance of common stock under employee stock plans, net of related tax benefits (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Net income Net income Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Current assets: Assets, Current [Abstract] Net put option fair value Options Derivative Liability Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes [Member] Foreign Currency Foreign Currency Transactions and Translations Policy [Policy Text Block] Entity Address, Address Line One Entity Address, Address Line One Total expenses Benefits, Losses and Expenses Vested (in 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 Line of Credit Facility, Fair Value of Amount Outstanding Line of Credit Facility, Fair Value of Amount Outstanding Income tax expense Income Tax Expense (Benefit) Loss contingency accrual, payments Loss Contingency Accrual, Payments Cost of products sold Cost of Product and Service Sold Award Timing Method Award Timing Method [Text Block] Change in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Premium receivables, net Premiums Receivable, Net Technology Infrastructure and Related Management and Support Services Technology Infrastructure and Related Management and Support Services [Member] Technology Infrastructure and Related Management and Support Services Shareholders’ net income Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Proceeds from issuance of common stock under employee stock plans Proceeds from Stock Options Exercised Exchange traded funds Exchange Traded Funds [Member] Total operating revenue Operating revenue - total Reportable segments’ operating revenue Operating Revenue Revenue from insurance services and products sold. Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Exercisable at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Receivables, net Increase (Decrease) in Receivables Class of Stock Disclosures [Abstract] Total Carelon Total Carelon [Member] Total Carelon Schedule of Investment Holdings, Other than Securities Investment Holdings, Other than Securities [Table Text Block] Proceeds from short-term borrowings Proceeds from Short-Term Debt Revenues Revenues [Abstract] Allowance for double accounts receivable recoveries Accounts Receivable, Allowance for Credit Loss, Recovery Category of Item Purchased [Axis] Category of Item Purchased [Axis] Basis Of Presentation And Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Other Invested Assets Other Long-Term Investments [Member] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract]