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Property, Plant, and Equipment Name Forgone Recovery, Individual Name Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Schedule of Receivables (Payables) Related to the Affordable Care Act Programs Schedule Of Receivables (Payables) Related To The Affordable Care Act Programs [Table Text Block] Schedule of Receivables (Payables) Related to the Affordable Care Act Programs Magellan Specialty Health Magellan Specialty Health [Member] Magellan Specialty Health Disposal Group Classification [Axis] Disposal Group Classification [Axis] Weighted average interest rate of outstanding borrowings Debt, Weighted Average Interest Rate The following table provides a reconciliation of cash, cash equivalents and restricted cash and cash equivalents reported within the Consolidated Balance Sheets to the totals above: Cash, 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Compensation Recovery [Table] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Title of 12(b) Security Title of 12(b) Security Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Global Intangible Low-Taxed Income (GILTI), percent Effective Income Tax Rate Reconciliation, GILTI, Percent Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Restricted cash equivalents Restricted Cash Equivalents [Member] Restricted Cash Equivalents [Member] Write-offs of uncollectible receivables Premium Receivable, Allowance for Credit Loss, Writeoff Net earnings (loss) per common share attributable to Centene Corporation: Net earnings (loss) per common share attributable to Centene Corporation: Earnings Per Share [Abstract] 2030 Lessee, Operating Lease, Liability, to be Paid, Year Five Paid related to: Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Net (loss) before equity in subsidiaries Net income (loss), including portion attributable to noncontrolling interest before equity in earnings from subsidiaries Net income (loss), including portion attributable to noncontrolling interest before equity in earnings from subsidiaries Unearned revenue Increase (Decrease) in Contract with Customer, Liability External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] Common stock repurchases (in shares) Total share repurchases (in shares) Treasury Stock, Shares, Acquired Schedule of Property Software and Equipment Depreciation Periods Schedule Of Property Software And Equipment Depreciation Periods [Table Text Block] Schedule Of Property Software And Equipment Depreciation Periods [Table Text Block] Award Timing Disclosures [Line Items] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Goodwill Impairment Loss Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag Goodwill Impairment Loss Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag Goodwill Impairment Loss Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag Balance, January 1, net Balance December 31, net Liability for Unpaid Claims and Claims Adjustment Expense, Net Recoveries Accounts Receivable, Allowance for Credit Loss, Recovery Payments for legal settlement Payments for Legal Settlements Stockholders' Equity Equity [Text Block] State and local Deferred State and Local Income Tax Expense (Benefit) Intangible assets, current Disposal Group, Including Discontinued Operation, Intangible Assets, Current Collaborative Health Systems Collaborative Health Systems [Member] Collaborative Health Systems Net earnings (loss) attributable to Centene Corporation Earnings (loss) attributable to Centene Corporation Net Income (Loss) Attributable to Parent Subsequent Event [Table] Subsequent Event [Table] Pending Litigation Pending Litigation [Member] Schedule of Reconciliation of Tax Provision at the U.S. Federal Statutory Rate to Income Tax Expense Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Stock options, restricted stock and restricted stock unit awards vesting period, years Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Return of premium payable Return of Premium Payable Return of Premium Payable Other, percent Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Preferred stock, shares authorized (in shares) Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Common stock repurchases Common stock repurchases Payments for Repurchase of 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aggregate statutory capital and surplus Statutory Accounting Practices, Statutory Capital and Surplus Required Risk adjustment, net payable Affordable Care Act, Risk Adjustment, Net Payable Affordable Care Act, Risk Adjustment, Net Payable Other income (expense) Other Nonoperating Income (Expense) Statement [Table] Statement [Table] Deferred income taxes Deferred Income Tax Expense (Benefit) Adjustments to reconcile net earnings (loss) to net cash provided by operating activities Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Statute of limitation lapses Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Short-duration Insurance Contracts, Accident Year [Axis] Short-Duration Insurance Contracts, Accident Year [Axis] Cash flows from financing activities: Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Shares used in computing per share amounts: Earnings Per Share, Basic, Other Disclosure [Abstract] Other jurisdictions Foreign Tax Jurisdiction, Other [Member] Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Amendment Flag Amendment Flag Income tax benefit recognized Share-Based Payment Arrangement, Expense, Tax Benefit Accrued interest income Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss Medical claims liability Balance, January 1 Balance, December 31 Liability for Claims and Claims Adjustment Expense Treasury stock, at cost (131,706 and 124,288 shares, respectively) Treasury Stock, Common, Value Termination Date Trading Arrangement Termination Date Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Weighted average discount rate for operating leases Operating Lease, Weighted Average 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[Abstract] Debt Disclosure [Abstract] Other income (expense): Other income (expense): Nonoperating Income (Expense) [Abstract] Medical Claims Liability Unpaid Policy Claims and Claims Adjustment Expense, Policy [Policy Text Block] Change in unrealized gain (loss) on investments OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Consolidated Entities [Axis] Consolidated Entities [Axis] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in usd per share) Common stock, par value (in usd per share) Common Stock, Par or Stated Value Per Share Schedule of Amortization Period for Intangible Assets Schedule Of Amortization Period For Intangible Assets [Table Text Block] Schedule Of Amortization Period For 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Resulting from Current Period Tax Positions Debt redemption amount Debt Instrument, Repurchased Face Amount Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Asset-backed securities Asset-backed securities Asset-Backed Securities [Member] Debt issuance costs Unamortized Debt Issuance Expense Consolidation Items [Axis] Consolidation Items [Axis] Schedule of Non-Vested Restricted Stock and Restricted Stock Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Medicaid Medicaid Medicaid Segment [Member] Medicaid Segment Purchased contract rights and customer relationships Purchased contract rights and customer relationships Customer Contracts [Member] Net earnings (loss) Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate securities Corporate securities Corporate Debt Securities [Member]