Debt Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Domain] Property Subject to or Available for Operating Lease [Domain] Property Subject to Operating Lease Property Subject to Operating Lease [Member] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] 6th & Pine Development, LLC 6th & Pine Development, LLC [Member] 6th & Pine Development, LLC [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Construction in Progress Construction in Progress [Member] Sale Leaseback Transaction, Description [Axis] Sale Leaseback Transaction, Description [Axis] Sale Leaseback Transaction, Name [Domain] Sale Leaseback Transaction, Name [Domain] June 2013 Transactions June 2013 Transactions [Member] June 2013 Transactions February 2013 Transactions February 2013 Transactions [Member] February 2013 Transactions Debt Instrument [Line Items] Debt Instrument [Line Items] Sale leaseback lease term Sale Leaseback Transaction, Term of Lease Sale Leaseback Transaction, Term of Lease Annual increase in rental payment (in percent) Sale Leaseback Transaction, Annual Rental Payments Increase Percentage Sale Leaseback Transaction, Annual Rental Payments Increase Percentage Interest expense related to lease financing obligations Interest Expense Number of properties Number of Property Leased Number of Property Leased Property, equipment, and capitalized software, net Property, Plant and Equipment, Net Lease financing obligation related to the construction projects Lease Financing Obligations Lease Financing Obligations Rent expense Sale Leaseback Transaction, Rent Expense Accounting Policies [Abstract] Schedule of Premium Revenue by Health Plan Type Schedule of Premium Revenue by Health Plan Type [Table] Schedule of premium revenue by health plan type. Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Health Plans Health Plans [Member] Health plans. Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] California CALIFORNIA Florida FLORIDA Illinois ILLINOIS Michigan MICHIGAN New Mexico NEW MEXICO Ohio OHIO Puerto Rico PUERTO RICO South Carolina SOUTH CAROLINA Texas TEXAS Utah UTAH Washington WASHINGTON Wisconsin WISCONSIN Direct delivery and other Other Health Plan [Member] Other health plan. Schedule of Premium Revenue by Health Plan Type [Line Items] Schedule of Premium Revenue by Health Plan Type [Line Items] Schedule of premium revenue by health plan type. Summarized premium revenue Health Care Organization, Revenue [Abstract] Premium revenue Health Care Organization, Premium Revenue Premium revenue percentage Health Care Organization, Revenue Percentage Health Care Organization, Revenue Percentage Earnings Per Share [Abstract] Net Income per Share Earnings Per Share [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Other Other Segments [Member] Goodwill [Line Items] Goodwill [Line Items] Changes in the carrying amount of goodwill Goodwill [Roll Forward] Goodwill, gross Goodwill, Gross Accumulated impairment losses Goodwill, Impaired, Accumulated Impairment Loss Acquisitions by Segment Goodwill, Other Changes Goodwill, net Goodwill Depreciation, and amortization of capitalized software, continuing operations Depreciation And Amortization Of Capitalized Software Depreciation, and amortization of capitalized software. Amortization of intangible assets, continuing operations Amortization of Intangible Assets Depreciation and amortization, continuing operations Depreciation and Amortization, Continuing Operations Depreciation and Amortization, Continuing Operations Amortization recorded as reduction of service revenue Cost of Services, Amortization Amortization of capitalized software recorded as cost of service revenue Cost Of Services Amortization Of Capitalized Software Cost of services amortization of capitalized software. Depreciation and amortization reported in the statement of cash flows Cost of Goods Sold, Depreciation and Amortization Variable Interest Entities [Abstract] Variable Interest Entities [Abstract] Variable Interest Entities Variable Interest Entity Disclosure [Text Block] Quarterly Financial Information Disclosure [Abstract] Quarterly Results of Operations (Unaudited) Quarterly Financial Information [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative [Table] Derivative [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] 1.125% Call Option Call Option, Derivative Asset [Member] Call Option, Derivative Asset [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 1.125% Cash Convertible Senior Notes due 2020 Cash Convertible Senior Notes due 2020 [Member] Cash Convertible Senior Notes due 2020 [Member] Derivative [Line Items] Derivative [Line Items] Fixed interest rate on derivative Derivative, Fixed Interest Rate Percentage of contractual interest rate Debt Instrument, Interest Rate, Stated Percentage Equity [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Stock options Employee Stock Option [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Stock options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Weighted-average grant date fair value of stock options granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Dividend yield (in percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted-average expected life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Total intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value State health plans with quality incentive programs California, Illinois, New Mexico, Ohio, South Carolina, Texas, Washington, and Wisconsin [Member] California, Illinois, New Mexico, Ohio, South Carolina, Texas, Washington, and Wisconsin [Member] Maximum available quality incentive premium - current period Maximum Available Quality Incentive Premium Current Year Maximum available quality incentive premium current year. Amount of quality incentive premium revenue recognized in current period - Earned current period Amount Of Current Year Quality Incentive Premium Revenue Recognized Amount of current year quality incentive premium revenue recognized. Amount of quality incentive premium revenue recognized in current period - Earned prior periods Amount Of Quality Incentive Premium Revenue Recognized From Prior Year Amount of quality incentive premium revenue recognized from prior year. Total quality incentive premium revenue recognized Quality Incentive Premium Revenue Recognized Quality incentive premium revenue recognized. Total premium revenue recognized for state health plans with quality incentive premiums Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2011 Plan Two Thousand And Eleven Plan [Member] Two thousand and eleven plan. Restricted shares Restricted Stock [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common Stock Common Stock [Member] Number of employee equity incentives plans Share-based Compensation Arrangement by Share-based Payment Award, Number of Plans Share-based Compensation Arrangement by Share-based Payment Award, Number of Plans Number of shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Maximum award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Stock option expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Share-based compensation, shares Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Postemployment Benefits [Abstract] Maximum matching contribution by employer under defined contribution plan Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Expense recognized in connection with contributions Defined Contribution Plan, Cost Recognized Deferred compensation plan deferral percentage of basic salary Deferred Compensation Plan Deferral Percentage Of Basic Salary Deferred compensation plan deferral percentage of basic salary. Deferred compensation plan deferral percentage of bonus Deferred Compensation Plan Deferral Percentage Of Bonus Deferred compensation plan deferral percentage of bonus. Condensed Financial Information of Parent Company Only Disclosure [Abstract] Schedule of Condensed Financial Statements [Table] Condensed Financial Statements [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Parent Company Parent Company [Member] Condensed Financial Statements, Captions [Line Items] Condensed Financial Statements, Captions [Line Items] Condensed Balance Sheets Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Investments Marketable Securities, Current Income tax refundable Income Taxes Receivable Due from affiliates Due from Affiliates Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Derivative asset Derivative Asset, Current Total current assets Assets, Current Goodwill and intangible assets, net Intangible Assets, Net (Including Goodwill) Investments in subsidiaries Investment In Subsidiaries Investment in subsidiaries. Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Derivative asset Derivative Asset, Noncurrent Advances to related parties and other assets Advances To Related Parties And Other Assets Advances to related parties and other assets. Total assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Liabilities: Liabilities, Current [Abstract] Accounts payable and accrued liabilities Accounts Payable, Current Long-term Debt, Current Maturities Long-term Debt, Current Maturities Derivative liability Derivative Liability, Current Total current liabilities Liabilities, Current Senior notes Long-term Debt Lease financing obligations Lease Financing Obligations, Noncurrent Lease Financing Obligations, Noncurrent Lease financing obligations - related party Due to Related Parties, Noncurrent Derivative liability Derivative Liability, Noncurrent Other long-term liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Common stock, $0.001 par value; 150 shares authorized; outstanding: 56 shares at December 31, 2015 and 50 shares at December 31, 2014 Common Stock, Value, Outstanding Preferred stock, $0.001 par value; 20,000 shares authorized, no shares issued and outstanding Preferred Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Retained earnings Retained Earnings (Accumulated Deficit) Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders' equity Liabilities and Equity Summary of denominators for the computation of basic and diluted earnings per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Investments, Debt and Equity Securities [Abstract] Contractual maturities of our held-to-maturity restricted investments Held-to-maturity Securities, Debt Maturities [Abstract] Amortized Cost, Due in one year or less Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount Amortized Cost, Due one year through five years Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount Amortized Cost, Total Held-to-maturity Securities Estimated Fair Value, Due in one year or less Held-to-maturity Securities, Debt Maturities, Next Twelve Months, Fair Value Estimated Fair Value, Due one year through five years Held-to-maturity Securities, Debt Maturities, Year Two Through Five, Fair Value Estimated Fair Value, Total Held-to-maturity Securities, Fair Value Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Table] Molina Medicaid Solutions Medicaid Solutions Segment [Member] Molina Medicaid solutions segment. Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Other Operating Segment Reconciling Items [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Number of reportable segments Number of Reportable Segments Total revenue Revenues Gross Profit Gross Profit Other operating expenses Costs and Expenses Operating income Operating Income (Loss) Other expenses, net Nonoperating Income (Expense) Income from continuing operations before income tax expense Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Depreciation and amortization Depreciation, Depletion and Amortization Goodwill and intangible assets, net Goodwill And Intangible Assets Net Goodwill and intangible assets net. Total assets Significant Accounting Policies Significant Accounting Policies [Text Block] Long-Term Debt Long-term Debt [Text Block] Property, Plant and Equipment [Abstract] Property, Equipment, and Capitalized Software Property, Plant and Equipment Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Condensed Balance Sheets Condensed Balance Sheet [Table Text Block] Condensed Statements of Income Condensed Income Statement [Table Text Block] Condensed Statements of Comprehensive Income Comprehensive Income (Loss) [Table Text Block] Condensed Statements of Cash Flows Condensed Cash Flow Statement [Table Text Block] Summary of restricted investments by health plan Schedule of Balances of Restricted Investments by Health Plan [Table Text Block] Schedule of balances of restricted investments by health plan. Contractual maturities of our held-to-maturity restricted investments Investments Classified by Contractual Maturity Date Held To Maturity Restricted Investments [Table Text Block] Investments classified by contractual maturities of our held-to-maturity restricted investments. Condensed Statements of Income Income Statement [Abstract] Revenue: Revenues [Abstract] Management fees and other operating revenue Management Fees Revenue Investment income Investment Income, Net Total revenue Expenses: Operating Expenses [Abstract] Medical care costs Health Care Organization, Expenses, Net General and administrative expenses General and Administrative Expense Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Total operating expenses Operating income Interest expense Interest and Debt Expense Other expense, net Other Expenses Loss before income taxes and equity in net income of subsidiaries Loss Before Income Taxes And Equity In Net Income Of Subsidiaries Loss before income taxes and equity in net income of subsidiaries. Income tax benefit Income Tax Expense (Benefit) Net loss before equity in net income of subsidiaries Net Loss Before Equity In Net Income Of Subsidiaries Net loss before equity in net income of subsidiaries. Equity in net income of subsidiaries Equity In Net Income Of Subsidiaries Equity in net income of subsidiaries. Net income Net Income (Loss) Attributable to Parent Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Integral Health Plan, Inc. Integral Health Plan, Inc. [Member] Integral Health Plan, Inc. [Member] Preferred Medical Plan, Inc. Preferred Medical Plan, Inc. [Member] Preferred Medical Plan, Inc. [Member] HealthPlus of Michigan and HealthPlus Partners, Inc. HealthPlus Of Michigan And HealthPlus Partners, Inc. [Member] HealthPlus Of Michigan And HealthPlus Partners, Inc. [Member] Business acquisitions during year excluding Pathways Integral Health Plan, Preferred Medical Plan, HealthPlus Of Michigan And HealthPlus Partners Acquisitions [Member] Integral Health Plan, Preferred Medical Plan, HealthPlus Of Michigan And HealthPlus Partners Acquisitions [Member] Pathways Health and Community Support LLC Pathways Health And Community Support LLC [Member] Pathways Health And Community Support LLC [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Contractual rights and licenses Contract Rights and Licensing Agreements [Member] Contract Rights and Licensing Agreements [Member] Provider network Provider Networks [Member] Provider networks. Business Acquisition [Line Items] Business Acquisition [Line Items] Purchase price Business Combination, Consideration Transferred Number of members added, approximately Number of Members Added Number of Members Added Consideration withheld to establish an indemnification amount (as a percent) Business Combination, Contingent Consideration, Liability, As A Percentage Of Purchase Price Business Combination, Contingent Consideration, Liability, As A Percentage Of Purchase Price Consideration withheld to establish an indemnification amount Business Combination, Contingent Consideration, Liability Goodwill acquired during period Goodwill, Acquired During Period Consideration recorded to prepaid expense and other assets Number of States in which company operates (states) Number of States in which Entity Operates Portion of goodwill acquired that is tax deductible Business Acquisition, Goodwill, Expected Tax Deductible Amount, Percent Business Acquisition, Goodwill, Expected Tax Deductible Amount, Percent Gross contractual amount of receivables Business Combination, Acquired Receivables, Gross Contractual Amount Estimated contractual cash flows not expected to be collected for receivables Business Combination, Acquired Receivables, Estimated Uncollectible Transaction costs expensed Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed Weighted-average amortization period for intangible assets Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Other Liabilities Disclosure [Abstract] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Balance at beginning of period Liability for Claims and Claims Adjustment Expense Components of medical care costs related to: Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract] Current period Current Year Claims and Claims Adjustment Expense Prior periods Prior Year Claims and Claims Adjustment Expense Total medical care costs Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Change in non-risk provider payables Medical Claims and Benefits Payable, Adjustments, Change in Provider Medical Claims and Benefits Payable, Adjustments, Change in Provider Payments for medical care costs related to: Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Current period Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year Prior periods Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years Total paid Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Balance at end of period Employee stock purchase plan and stock options Employee Stock Purchase Plan and Stock Options [Member] Employee Stock Purchase Plan and Stock Options [Member] Stock based compensation expense Share-based Compensation [Abstract] Stock based compensation expense, Pretax charges Allocated Share-based Compensation Expense Stock based compensation expense, Net-of-Tax Amount Allocated Share-based Compensation Expense, Net of Tax Unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted average period of unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Unrecognized compensation forfeited rate Unrecognized Compensation Forfeited Rate Unrecognized compensation forfeited rate. Receivables Receivables, Net, Current Income taxes refundable Income Taxes Receivable, Current Property, equipment, and capitalized software, net Deferred contract costs Costs in Excess of Billings, Noncurrent Intangible assets, net Finite-Lived Intangible Assets, Net Goodwill Restricted investments Restricted Investments, Noncurrent Deferred income taxes Deferred Tax Assets, Net, Noncurrent Other assets Other Assets, Noncurrent Current liabilities: Medical claims and benefits payable Amounts due government agencies Medical Premium Liability Due to Agency Medical Premium Liability Due to Agency Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities, Current Deferred revenue Deferred Revenue, Current Income taxes payable Accrued Income Taxes, Current Current maturities of long-term debt Senior notes Convertible Notes Payable, Noncurrent Other long-term liabilities Preferred stock, $0.001 par value; 20 shares authorized, no shares issued and outstanding Additional paid-in capital Retained earnings Commitments and Contingencies Disclosure [Abstract] Summary of future minimum lease payments Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Preferred Stock, Par or Stated Value Per Share Preferred Stock, Par or Stated Value Per Share Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Preferred Stock, Shares Issued Preferred Stock, Shares Issued Preferred Stock, Shares Outstanding Preferred Stock, Shares Outstanding Medical Care Costs Health Care Organization, Expenses, Gross [Abstract] Fee-for-service Health Care Organization Expenses Servicing Cost Health care organization expenses fee for service costs. Pharmacy Health Care Organization, Medical Supplies and Drugs Expense Capitation Health Care Organization Expenses Capitation Costs Health care organization expenses capitation costs. Direct delivery Health Care Organization, Direct Delivery Expense Health Care Organization, Direct Delivery Expense Other Health Care Organization Expenses Other Costs Health care organization expenses other costs. Total Health Care Organization, Expenses, Gross Medical Care Costs, PMPM Health Care Organization, Expenses, Per Member Per Month [Abstract] Health Care Organization, Expenses, Per Member Per Month [Abstract] Fee-for-service (per member per month) Health Care Organization Expenses Servicing Cost, Per Member Per Month Health Care Organization Expenses Servicing Cost, Per Member Per Month Pharmacy (per member per month) Health Care Organization, Medical Supplies and Drugs Expense, Per Member Per Month Health Care Organization, Medical Supplies and Drugs Expense, Per Member Per Month Capitation (per member per month) Health Care Organization Expenses Capitation Costs, Per Member Per Month Health Care Organization Expenses Capitation Costs, Per Member Per Month Direct delivery (per member per month) Health Care Organization, Direct Delivery Expense, Per Member Per Month Health Care Organization, Direct Delivery Expense, Per Member Per Month Other (per member per month) Health Care Organization Expenses Other Costs, Per Member Per Month Health Care Organization Expenses Other Costs, Per Member Per Month Total (per member per month) Health Care Organization, Expenses, Gross, Per Member Per Month Health Care Organization, Expenses, Gross, Per Member Per Month Medical Care Costs, Percentage Health Care Organization, Expenses, Percentage [Abstract] Health Care Organization, Expenses, Percentage [Abstract] Percentage of total in Fee for service Percentage Of Fee For Service Percentage of fee for service. Percentage of total in pharmacy Percentage Of Pharmacy Percentage of pharmacy. Percentage of total in capitation Percentage Of Capitation Percentage of capitation. Percent of total in direct delivery Percent of Direct Delivery Percent of Direct Delivery Percentage of total in other Percentage Of Other Percentage of other. Percentage of total Percentage Of Medical Costs Percentage of medical costs. Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Operating segment information Schedule of Segment Reporting Information, by Segment [Table Text Block] Effective income tax rate reconciliation to the statutory federal income tax rate Effective Income Tax Rate Reconciliation, Amount [Abstract] Statutory federal tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Change in unrecognized tax benefits Effective Income Tax Rate Reconciliation, Tax Contingency, Percent Nondeductible health insurer fee (HIF) Effective Income Tax Rate Reconciliation, Nondeductible Expense, Health Insurance, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Health Insurance, Percent Nondeductible compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent Nondeductible fair value of 1.125% Warrants Effective Income Tax Rate Reconciliation, Nondeductible Expense, Warrants, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Warrants, Percent Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective tax rate Effective Income Tax Rate Reconciliation, Percent Summary of future minimum rentals on non cancelable leases Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract] 2016 Capital Leases, Future Minimum Payments Receivable, Next Twelve Months 2017 Capital Leases, Future Minimum Payments, Receivable in Two Years 2018 Capital Leases, Future Minimum Payments, Receivable in Three Years 2019 Capital Leases, Future Minimum Payments, Receivable in Four Years 2020 Capital Leases, Future Minimum Payments, Receivable in Five Years Thereafter Capital Leases, Future Minimum Payments, Receivable Thereafter Total minimum future rentals Capital Leases, Future Minimum Payments Receivable Schedule of Operating Leases Future Minimum Payments [Table] Schedule of Operating Leases Future Minimum Payments [Table] Schedule of Operating Leases Future Minimum Payments [Table] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Axis] Lease Arrangement, Type [Domain] Lease Arrangement, Type [Domain] Lease Financing Obligations Lease Financing Obligations [Member] Lease Financing Obligations [Member] Operating Leases Operating Leases [Member] Operating Leases [Member] Schedule of Operating Leases Future Minimum Payments [Line Items] Schedule of Operating Leases Future Minimum Payments [Line Items] [Line Items] for Schedule of Operating Leases Future Minimum Payments [Table] Summary of future minimum lease payments Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2016 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2017 Operating Leases, Future Minimum Payments, Due in Two Years 2018 Operating Leases, Future Minimum Payments, Due in Three Years 2019 Operating Leases, Future Minimum Payments, Due in Four Years 2020 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total minimum lease payments Operating Leases, Future Minimum Payments Due Schedule Of Maturities Of Long Term Debt [Table] Schedule Of Maturities Of Long Term Debt [Table] Schedule of maturities of long term debt. 5.375% Notes Senior Notes Due 2022 [Member] Senior Notes Due 2022 [Member] 1.125% Convertible Notes 1.625% Convertible Notes Convertible Senior Notes Due 2044 [Member] Convertible Senior Notes Due 2044 [Member] Other Other Debt [Member] Other Debt [Member] Maturities Of Long Term Debt [Line Items] Maturities Of Long Term Debt [Line Items] Maturities of long-term debt. Maturities of Long-term Debt [Abstract] Maturities of Long-term Debt [Abstract] Net carrying amount Long-term Debt, Gross 2016 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2017 Long-term Debt, Maturities, Repayments of Principal in Year Two 2018 Long-term Debt, Maturities, Repayments of Principal in Year Three 2019 Long-term Debt, Maturities, Repayments of Principal in Year Four 2020 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Corporate Debt Securities Corporate Debt Securities [Member] GSEs US Government-sponsored Enterprises Debt Securities [Member] Municipal Securities Municipal Securities [Member] Municipal securities. Certificates of Deposit Certificates of Deposit [Member] US Treasury Notes Securities US Treasury Notes Securities [Member] Asset-backed Securities Asset-backed Securities [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Investments Schedule Of Available For Sale Securities Reconciliation [Abstract] Schedule of available for sale securities reconciliation. Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Estimated Fair Value Available-for-sale Securities Segment Information Segment Reporting Disclosure [Text Block] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Contract licenses Licensing Agreements [Member] Contract rights - member list Customer Contracts [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Fair value of intangible assets acquired Finite-lived Intangible Assets Acquired Provision for income taxes Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Total current Current Income Tax Expense (Benefit) Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Foreign Deferred Foreign Income Tax Expense (Benefit) Total deferred Deferred Income Tax Expense (Benefit) Total provision for income taxes Condensed Financial Statements [Table] Net income Unrealized investment loss Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Effect of income tax benefit Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Fair value of assets measured on recurring basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Fair value measurements of senior notes Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Common stock, par value Common stock, shares outstanding Preferred stock, par value Preferred stock, shares authorized Preferred stock, shares issued Preferred stock, shares outstanding Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Services revenue from subsidiaries Revenue from Related Parties Medical Claims and Benefits Payable Medical Claims And Benefits Payable [Text Block] Medical claims and benefits payable. Depreciation and amortization Depreciation And Amortization [Table Text Block] Depreciation and amortization. Summarized premium revenue Summarized Premium Revenue [Table Text Block] summarized premium revenue. Receivables (payables) for 3R programs Affordable Care Act, Premium Stabilization Programs, Receivables and Payables [Table Text Block] Affordable Care Act, Premium Stabilization Programs, Receivables and Payables [Table Text Block] Quality incentive premium revenue recognized Quality Incentive Premium Revenue Recognized [Table Text Block] Quality incentive premium revenue recognized. Consolidated medical care costs Schedule Of Health Care Organization Cost [Table Text Block] Schedule of health care organization cost. Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Depreciation expense recognized Depreciation Amortization of capitalized software Amortization Schedule of Indefinite-lived Intangible Assets by Major Class [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets by Major Class [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Customer relationships Customer Relationships [Member] Contract backlog Order or Production Backlog [Member] Indefinite-lived Intangible Assets by Major Class [Line Items] Indefinite-lived Intangible Assets [Line Items] Summary of identified intangible assets Finite-Lived Intangible Assets, Net [Abstract] Intangible Assets, Net (Excluding Goodwill) [Abstract] Intangible Assets, Net (Excluding Goodwill) [Abstract] Cost Finite-Lived Intangible Assets, Gross Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Net balance Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Fee-for-service claims incurred but not paid (IBNP) Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount Pharmacy payable Pharmacy Claims Payable Pharmacy Claims Payable Capitation payable Capitation Claims Payable Capitation Claims Payable Other Other Claims Payable Other Claims Payable Medical claims and benefits payable Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Eligible Item or Group for Fair Value Option [Axis] Eligible Item or Group for Fair Value Option [Axis] Fair Value, Option, Eligible Item or Group [Domain] Fair Value, Option, Eligible Item or Group [Domain] Government-sponsored enterprise securities (GSEs) Current Investments Current Investments [Member] Current Investments [Member] 1.125% Call Option Derivative Asset Derivative Financial Instruments, Assets [Member] 1.125% Notes Conversion Option Embedded Derivative Financial Instruments [Member] 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 of assets measured on recurring basis Assets, Fair Value Disclosure [Abstract] Total assets measured at fair value on a recurring basis Assets, Fair Value Disclosure 1.125% Conversion Option derivative liability Derivative Liability Total liabilities measured at fair value on a recurring basis Financial and Nonfinancial Liabilities, Fair Value Disclosure Restricted Investments Restricted Assets Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Retained Earnings Retained Earnings [Member] Treasury Stock Treasury Stock [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance, shares Shares, Outstanding Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Other comprehensive income, net Purchase of treasury stock, shares Treasury Stock, Shares, Acquired Purchase of treasury stock Treasury Stock, Value, Acquired, Cost Method Retirement of treasury stock Treasury Stock, Retired, Cost Method, Amount Shares issued in connection with conversions, shares Stock Issued During Period, Shares, Conversion of Convertible Securities Convertible senior notes transactions, including issuance costs Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature Issuance of warrants Adjustments to Additional Paid in Capital, Warrant Issued Common stock offering transaction, including issuance costs, shares Stock Issued During Period, Shares, New Issues Common stock offering transaction, including issuance costs Stock Issued During Period, Value, New Issues Share-based compensation Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Tax benefit from share-based compensation Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Ending Balance, shares Ending Balance Investments Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Contractual maturities of investments Investments Classified by Contractual Maturity Date [Table Text Block] Available-for-sale investments Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block] Schedule of Property, Plant and Equipment Property, Plant and Equipment [Table] Furniture and equipment Furniture and Fixtures [Member] Software Computer Software, Intangible Asset [Member] Leasehold Improvements Leasehold Improvements [Member] Building and improvements Building and Building Improvements [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Insurance-related Assessments Insurance-related Assessments [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Restatement Adjustment Restatement Adjustment [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Medical Premium Liability Due to Agency Medical Premium Liability Due to Agency [Member] Medical Premium Liability Due to Agency [Member] California, Illinois, New Mexico, Ohio, South Carolina, Texas, Washington, and Wisconsin Missouri MISSOURI Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Medicaid Expansion Medicaid Expansion [Member] Medicaid Expansion [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Maturity of cash and cash equivalents Maturity Of Cash And Cash Equivalents Maturity of cash and cash equivalents. Final maturities of investments Investments, Maturity Period Investments, Maturity Period Average maturity of investments Investments, Average Maturity Period Investments, Average Maturity Period Useful life of property plant and equipment Property, Plant and Equipment, Useful Life Weighted average amortization period Finite-Lived Intangible Asset, Useful Life Medical premium liability based on medical costs threshold Medical Premiums Liability, Medical Care Costs Threshold Medical Premiums Liability, Medical Care Costs Threshold Premiums receivable Premiums Receivable, Gross Profit sharing liability Medical Premiums Liability, Profit Sharing Threshold Medical Premiums Liability, Profit Sharing Threshold Reduction in revenues Loss contingency, portion not accrued Loss Contingency, Range of Possible Loss, Portion Not Accrued Maximum period for member risk scores and member pharmacy cost experience after original year of service Maximum Period For Member Risk Scores And Member Pharmacy Cost Experience After Original Year Of Service Maximum period for member risk scores and member pharmacy cost experience after original year of service. Anticipated Medicare risk adjustment premiums Anticipated Medicare Risk Adjustment Premiums Anticipated Medicare risk adjustment premiums. Payment of Medicaid Expansion medical cost floor liability Increase (Decrease) in Medical Premium Liability Due to Agency Increase (Decrease) in Medical Premium Liability Due to Agency Medical administrative costs Medical Administrative Costs Medical administrative costs. Goodwill impairment charges Goodwill, Impairment Loss Percentage of additional incremental revenue earned Percentage Of Additional Incremental Revenue Earned Percentage of additional incremental revenue earned. Concentration of credit risk Fair Value, Concentration of Risk, Investments Number of States Health Plans segments contracted with (states) Schedule of liability for unpaid claims and claims adjustment expense Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Components of the change in medical claims and benefits payable Components Of Change In Medical Claims And Benefits Payable [Table Text Block] Components Of Change In Medical Claims And Benefits Payable [Table Text Block] Receivables [Abstract] Schedule of Financing Receivables Past Due Schedule of Financing Receivables Past Due [Table] Molina Medicaid Solutions Segment Financing Receivable, Recorded Investment, Past Due [Line Items] Financing Receivable, Recorded Investment, Past Due [Line Items] Summary of accounts receivable Receivables, Net, Current [Abstract] Total receivables Business Combinations Business Combination Disclosure [Text Block] Statement of Comprehensive Income [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Maturities of long-term debt Schedule of Maturities of Long-term Debt [Table Text Block] Long term debt Schedule of Long-term Debt Instruments [Table Text Block] Debt instruments interest cost recognized Schedule Of Debt Instruments Interest Cost Recognized [Table Text Block] Schedule of debt instruments interest cost recognized. Derivatives Derivative Instruments and Hedging Activities Disclosure [Text Block] Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Investments Investment, Policy [Policy Text Block] Receivables Receivables, Policy [Policy Text Block] Property, Equipment, and Capitalized Software Property, Plant and Equipment, Policy [Policy Text Block] Depreciation and Amortization Depreciation, Depletion, and Amortization [Policy Text Block] Long-Lived Assets, including Intangible Assets Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Business Combinations Business Combinations Policy [Policy Text Block] Restricted Investments Restricted Investments [Policy Text Block] Restricted investments. Delegated Provider Insolvency Delegated Provider Insolvency [Policy Text Block] Delegated provider insolvency. Premium Revenue - Health Plans Premium Revenue [Policy Text Block] Premium revenue. Medical Care Costs - Health Plans Health Care Costs, Policy [Policy Text Block] Taxes Based on Premiums Taxes Based On Premiums [Policy Text Block] Taxes based on premiums. Premium Deficiency Reserves on Loss Contracts Premium Deficiency Reserves on Loss Contracts [Policy Text Block] Premium Deficiency Reserves on Loss Contracts [Policy Text Block] Service Revenue and Cost of Service Revenue - Molina Medicaid Solutions Service Revenue and Cost of Service Revenue Policy [Policy Text Block] Service Revenue and Cost of Service Revenue Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Concentrations of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Risks and Uncertainties Risks And Uncertainties [Policy Text Block] Risks and uncertainties. Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Receivables Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Sale Leaseback Transaction [Table] Sale Leaseback Transaction [Table] Termination of hospital management agreement Loss On Long-Term Management Agreement [Member] Loss On Long-Term Management Agreement [Member] Collectibility of premium receivables Collectibility of Receivables [Member] Executive Officer Executive Officer [Member] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Employment Contracts Employment Contracts [Member] Sale Leaseback Transaction [Line Items] Sale Leaseback Transaction [Line Items] Lease renewal terms Sale Leaseback Transaction, Lease Renewal Term Sale Leaseback Transaction, Lease Renewal Term Operating lease terms Lessee Leasing Arrangements, Operating Leases, Term of Contract Operating lease renewal options Operating Lease, Number of Renewal Option Operating Lease, Number of Renewal Option Rental expense related to leases Operating Leases, Rent Expense, Net Employment agreements terms Related Party Transaction, Terms Related Party Transaction, Terms Automatically extension term Related Party Transaction, Extension Term Related Party Transaction, Extension Term Period of employment agreements Period For Health and Welfare Benefits Under Employment Agreements For Termination Without Cause Period for health and welfare benefits under employment agreements for termination without cause. Settlement charge Loss Contingency, Loss in Period Number of members served, approximately Health Care Organization, Number of Members Health Care Organization, Number of Members Approximate premium revenue, monthly Health Care Organization, Premium Revenue, Average Monthly Health Care Organization, Premium Revenue, Average Monthly Premium revenue being withheld by Commonwealth Loss Contingency, Range of Possible Loss, Maximum Net assets of subsidiaries subject to restrictions Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries Cash and investments Restricted Cash and Investments, Current Aggregate statutory capital and surplus Statutory Accounting Practices, Statutory Capital and Surplus, Balance Required minimum statutory capital surplus Statutory Accounting Practices, Statutory Capital and Surplus Required Schedule of Held-to-maturity Securities Schedule of Held-to-maturity Securities [Table] Other Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Summary of restricted investments by health plan Restricted Cash and Investments, Noncurrent [Abstract] Restricted investments by health plan Condensed Financial Information of Registrant Condensed Financial Information of Parent Company Only Disclosure [Text Block] Document and Entity Information [Abstract] -- None. No documentation exists for this element. -- Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Deferred Compensation Arrangement with Individual, Share-based Payments, by Title of Individual [Axis] Title of Individual [Axis] Title of Individual with Relationship to Entity [Domain] Relationship to Entity [Domain] Performance and Restricted Units Restricted and Performance Stock [Member] Restricted and Performance Stock [Member] Performance Restricted Stock Performance Restricted Stock [Member] Performance Restricted Stock Total fair value of restricted and performance award granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Granted in Period Fair Value Share based compensation arrangement by share based payment award equity instruments other than options granted in period fair value. Restricted shares vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Restricted shares granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Weighted-average grant date fair value per share of the performance awards with vesting conditions based on TSR (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Restricted shares outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Restricted shares expected to vest (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested and Expected to Vest, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested and Expected to Vest, Outstanding, Number Stock based compensation expense (reversal) Restricted shares forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Restricted shares vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Risk adjustment Affordable Care Act, Premium Stabilization Program, Risk Adjustment, Receivable (Payable) Affordable Care Act, Premium Stabilization Program, Risk Adjustment, Receivable (Payable) Reinsurance Affordable Care Act, Premium Stabilization Program, Reinsurance, Receivable (Payable) Affordable Care Act, Premium Stabilization Program, Reinsurance, Receivable (Payable) Risk corridor Affordable Care Act, Premium Stabilization Program, Risk Corridor, Receivable (Payable) Affordable Care Act, Premium Stabilization Program, Risk Corridor, Receivable (Payable) Minimum MLR Affordable Care Act, Premium Stabilization Program, Minimum Medical Loss Ratio, Receivable (Payable) Affordable Care Act, Premium Stabilization Program, Minimum Medical Loss Ratio, Receivable (Payable) Provision for income taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Effective income tax rate reconciliation to the statutory federal income tax rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Significant components of deferred tax assets and liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Unrecognized tax benefits roll forward Summary of Income Tax Contingencies [Table Text Block] Condensed Statements of Cash Flows Statement of Cash Flows [Abstract] Operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Capital contributions to subsidiaries Net Dividends From And Capital Contributed To Subsidiaries Net dividends from and capital contributed to subsidiaries. Dividends received from subsidiaries Proceeds from Dividends Received Purchases of investments Payments to Acquire Investments Proceeds from sales and maturities of investments Proceeds from Maturities, Prepayments and Calls of Other Investments Purchases of equipment Payments to Acquire Productive Assets Change in amounts due to/from affiliates Changes In Amounts Due To And Due From Affiliates Changes in amounts due to and due from affiliates. Other, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from senior notes offerings, net of issuance costs Proceeds from Issuance of Long-term Debt Proceeds from common stock offering, net of issuance costs Proceeds from Issuance of Common Stock Proceeds from sale-leaseback transactions Sale Leaseback Transaction, Gross Proceeds, Financing Activities Purchase of call option Payments for Derivative Instrument, Financing Activities Proceeds from issuance of warrants Proceeds from Issuance of Warrants Treasury stock purchases Payments for Repurchase of Common Stock Principal payment on term loan of subsidiary Repayments of Long-term Debt Repayment of amount borrowed under credit facility Repayments of Long-term Lines of Credit Proceeds from employee stock plans Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Principal payments on convertible senior notes Repayments of Convertible Debt Other, net Proceeds from (Payments for) Other Financing Activities Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Summary of quarterly results of operations Schedule of Quarterly Financial Information [Table Text Block] Insurance Claims [Table] Insurance Claims [Table] Insurance Claims [Table] MMP Program MMP Integrated Dual [Member] MMP Integrated Dual [Member] Insurance Claims [Line Items] Insurance Claims [Line Items] Insurance Claims [Line Items] Medical claims and benefits payable Medical Claims and Benefits Payable Medical Claims and Benefits Payable Estimated discount percentage of final payment on claims incurred but not paid Claims Incurred But Not Paid (IBNP) Liability, Estimated Discount Percentage of Final Payment Claims Incurred But Not Paid (IBNP) Liability, Estimated Discount Percentage of Final Payment Prior period claims expense (benefit) recognized Income (loss) from discontinued operations, tax expense (benefit) Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis Of Presentation [Table] Basis Of Presentation [Table] Basis Of Presentation [Table] Forecast Scenario, Forecast [Member] New Jersey NEW JERSEY Medicaid Medicaid [Member] Medicaid [Member] Medicare-Medicaid Plans (MMP) Medicare-Medicaid Plans [Member] Medicare-Medicaid Plans [Member] Loyola Physician Partners, LLC Loyola Physician Partners, LLC [Member] Loyola Physician Partners, LLC [Member] Better Health Network, LLC Better Health Network, LLC [Member] Better Health Network, LLC [Member] Accountable Care Chicago, LLC Accountable Care Chicago, LLC [Member] Accountable Care Chicago, LLC [Member] Columbia United Providers, Inc. Columbia United Providers, Inc. [Member] Columbia United Providers, Inc. [Member] Molina Medicaid Solutions Molina Medicaid Solutions [Member] Molina Medicaid Solutions. HAP Midwest Health Plan, Inc. HAP Midwest Health Plan, Inc. [Member] HAP Midwest Health Plan, Inc. [Member] Basis Of Presentation [Line Items] Basis Of Presentation [Line Items] Basis Of Presentation [Line Items] Number of members eligible for the health care programs Number of Members Eligible for the Health Care programs Number of members eligible for the health care programs. Minimum contract terms Minimum Contract Term Minimum contract term. Maximum contract terms Maximum Contract Term Maximum contract term. Tax benefit from stock abandon Discontinued Operation, Tax (Expense) Benefit from Stock Abandon Discontinued Operation, Tax (Expense) Benefit from Stock Abandon Contract terms Health Care Organization, Contract Terms Health Care Organization, Contract Terms Number of renewal Option Health Care Organization, Renewal Option Health Care Organization, Renewal Option Renewal period Health Care Organization, Renewal Period Health Care Organization, Renewal Period Increase in number of counties in which Company operates Increase In Number Of Counties In Which Entity Operates Increase In Number Of Counties In Which Entity Operates Revenue: Service revenue Technology Services Revenue Premium tax revenue Health Care Organization, Premium Tax Revenue Health Care Organization, Premium Tax Revenue Health insurer fee revenue Health Care Organization, Insurer Fee Revenue Health Care Organization, Insurer Fee Revenue Investment income Interest and Dividend Income, Operating Other revenue Health Care Organization, Other Revenue Operating expenses: Costs and Expenses [Abstract] Medical care costs Policyholder Benefits and Claims Incurred, Net, Health Cost of service revenue Technology Services Costs Premium tax expenses Premium Tax Expenses An assessment levied by a state government on the net premium income collected. Health insurer fee expenses Health Care Organization, Insurer Fee Expense Health Care Organization, Insurer Fee Expense Depreciation and amortization Interest expense Other (income) expense, net Other Nonoperating Income (Expense) Total other expenses, net Income tax expense Income from continuing operations Income (Loss) from Continuing Operations Attributable to Parent Income from discontinued operations, net of tax expense (benefit) of $0, $0, and $(10), respectively Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Basic net income per share: Income from continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Per Basic Share (Loss) income from discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Basic net income per share (in dollars per share) Earnings Per Share, Basic Diluted net income per share: Earnings Per Share, Diluted [Abstract] Income from continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Per Diluted Share (Loss) income from discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Diluted net income per share (in dollars per share) Earnings Per Share, Diluted Weighted average shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Provider Agreement with Pacific Healthcare IPA Provider Agreement With Pacific Healthcare IPA [Member] Provider Agreement With Pacific Healthcare IPA [Member] Pacific Healthcare IPA Affiliated Entity [Member] Ownership percentage Equity Method Investment, Ownership Percentage Payments under provider agreement Related Party Transaction, Amounts of Transaction Available-for-sale investments Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value In a Continuous Loss Position for Less than 12 Months, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Number of Positions, 12 Months or Less ( in security) Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year In a Continuous Loss Position for 12 Months or More, Estimated Fair value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value In a Continuous Loss Position for 12 Months or More, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Number of Positions, 12 Months or More ( in security) Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year Summary of property and equipment Property, Plant and Equipment [Table Text Block] Summary of future minimum rentals on noncancelable leases Schedule Of Future Minimum Rentals Table [Text Block] Schedule of future minimum rentals. Contractual maturities of investments Available-for-sale Securities, Debt Maturities [Abstract] Due in one year or less, Amortized Cost Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis Due after one year through five years, Amortized Cost Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis Due after five years through ten years, Amortized Cost Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis Due in one year or less, Estimated Fair Value Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Due after one year through five years, Estimated Fair Value Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value Due after five years through ten years, Estimated Fair Value Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value Total, Estimated fair value Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value Summary of identified intangible assets, by major class Schedule of Finite-Lived Intangible Assets [Table Text Block] Changes in the carrying amount of goodwill Schedule of Intangible Assets and Goodwill [Table Text Block] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] State State and Local Jurisdiction [Member] Foreign Foreign Tax Authority [Member] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Excess tax benefits from share-based compensation Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net Net operating loss carryforwards Operating Loss Carryforwards Tax credit carryovers Tax Credit Carryforward, Amount Deferred tax assets Tax Credit Carryforward, Valuation Allowance Increase in deferred tax asset valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Valuation allowance Deferred Tax Assets, Valuation Allowance Impact on effective tax rate if tax benefits are recognized Unrecognized Tax Benefits that Would Impact Effective Tax Rate Liability for unrecognized tax benefits Decrease in Unrecognized Tax Benefits is Reasonably Possible Gain on 1.125% Notes Call Option Loss on 1.125% Notes Conversion Option Loss on 1.125% Warrants Warrant [Member] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Deferred income taxes Increase (Decrease) in Deferred Income Taxes Share-based compensation Share-based Compensation Amortization of convertible senior notes and lease financing obligations Amortization of Debt Discount (Premium) and Sale Leaseback Financing Obligation Amortization of Debt Discount (Premium) and Sale Leaseback Financing Obligation Other, net Other Operating Activities, Cash Flow Statement Changes in operating assets and liabilities, net of effects from acquisitions: Increase (Decrease) in Operating Capital [Abstract] Receivables Increase (Decrease) in Receivables Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Medical claims and benefits payable Increase (Decrease) in Health Care Insurance Liabilities Amounts due government agencies Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Income taxes Increase (Decrease) in Income Taxes Payable Net cash provided by operating activities Purchases of investments Payments to Acquire Marketable Securities Proceeds from sales and maturities of investments Proceeds from Sale and Maturity of Marketable Securities Purchases of equipment Payments to Acquire Machinery and Equipment Increase in restricted investments Increase (Decrease) of Restricted Investments Net cash paid in business combinations Payments to Acquire Businesses, Net of Cash Acquired Other, net Payments for (Proceeds from) Other Investing Activities Contingent consideration liabilities settled Payments to Acquire Business Two, Net of Cash Acquired Principal payments on term loan Proceeds from employee stock plans Supplemental cash flow information: Supplemental Cash Flow Information [Abstract] Income taxes Income Taxes Paid, Net Interest Interest Paid Schedule of non-cash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Senior notes exchange transaction Notes Issued Retirement of treasury stock Retirement Of Treasury Stock Retirement of treasury stock. Increase in non-cash lease financing obligation - related party Construction in Progress Expenditures Incurred but Not yet Paid Common stock used for stock-based compensation Stock Issued Details of business combinations: Details of Business Combinations Abstract Details of business combinations: Fair value of assets acquired Fair Value of Assets Acquired Fair value of liabilities assumed Liabilities Assumed Fair value of contingent consideration liabilities incurred Business Combination, Contingent Consideration Accrual Business Combination, Contingent Consideration Accrual Payable to seller Supplemental Deferred Purchase Price Amounts advanced for acquisitions Business Combination, Prepaid Consideration Transferred Business Combination, Prepaid Consideration Transferred Details of change in fair value of derivatives, net: Details of change in fair value of derivatives [Abstract] Details of change in fair value of derivatives Change in fair value of derivatives, net Derivative, Gain (Loss) on Derivative, Net Summary of accounts receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Unrecognized tax benefits roll forward Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Gross unrecognized tax benefits at beginning of period Unrecognized Tax Benefits Increases in tax positions for current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Increases in tax positions for prior years Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Decreases in tax positions for prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Settlements Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Gross unrecognized tax benefits at end of period Class of Treasury Stock Class of Treasury Stock [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] December 2015 Repurchase Program December 2015 Repurchase Program [Member] December 2015 Repurchase Program [Member] February 2015 Repurchase Program February 2015 Repurchase Program [Member] February 2015 Repurchase Program [Member] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Stockholders' equity increased during the period Stockholders' Equity, Period Increase (Decrease) Increase to stockholders' equity due to share-based compensation transactions Stock Issued During Period, Value, and Income Tax Benefit Related to Share-based Compensation Stock Issued During Period, Value, and Income Tax Benefit Related to Share-based Compensation Shares issued in public offering (in shares) Offering price (USD per share) Share Price Trading days measurement period (in days) Class of Warrant or Right, Trading Days Measurement Period Class of Warrant or Right, Trading Days Measurement Period Number of warrants issued Debt Conversion, Converted Instrument, Warrants or Options Issued Striking price of Warrants (USD per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Stated interest rate for Warrants Class of Warrant or Right, Stated Percentage Class of Warrant or Right, Stated Percentage Threshold percentage of stock price trigger (percent) Class of Warrant or Right, Threshold Percentage of Stock Price Trigger Class of Warrant or Right, Threshold Percentage of Stock Price Trigger Approved amount related to stock repurchase program Stock Repurchase Program, Authorized Amount Issued shares of common stock, net of shares used to settle employees’ income tax obligations Principal amount Unamortized discount Debt Instrument, Unamortized Discount (Premium), Net Unamortized issuance costs Deferred Finance Costs, Net Net carrying amount Investments Marketable Securities [Table Text Block] Future Amortization Expenses Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Future amortization expense, 2016 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Future amortization expense, 2017 Finite-Lived Intangible Assets, Amortization Expense, Year Two Future amortization expense, 2018 Finite-Lived Intangible Assets, Amortization Expense, Year Three Future amortization expense, 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Four Future amortization expense, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Five Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility [Member] Revolving Credit Facility [Member] Letter of Credit [Member] Letter of Credit [Member] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Redemption period, option one Debt Instrument, Redemption Period, Option One [Member] Debt Instrument, Redemption Period, Option One [Member] Redemption period, option two Debt Instrument, Redemption Period, Option Two [Member] Debt Instrument, Redemption Period, Option Two [Member] August 19, 2018 Debt Instrument, Redemption, Period One [Member] August 19, 2024 Debt Instrument, Redemption, Period Two [Member] August 19, 2029 Debt Instrument, Redemption, Period Three [Member] August 19, 2034 Debt Instrument, Redemption, Period Four [Member] August 19, 2039 Debt Instrument, Redemption, Period Five [Member] Debt Conversion Description [Axis] Debt Conversion Description [Axis] Debt Conversion, Name [Domain] Debt Conversion, Name [Domain] 3.75% Convertible Note Exchange 3.75% Convertible Note Exchange [Member] 3.75% Convertible Note Exchange [Member] Extinguishment of Debt [Axis] Extinguishment of Debt [Axis] Extinguishment of Debt, Type [Domain] Extinguishment of Debt, Type [Domain] Convertible Debt Convertible Debt [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Unsecured Debt [Member] Unsecured Debt [Member] Senior Notes Senior Notes [Member] 5.375% Senior Notes due 2022 3.75% Convertible Senior Notes due 2014 Convertible Senior Notes due 2014 [Member] Convertible Senior Notes due 2014 [Member] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Term of debt instrument Debt Instrument, Term Potential maximum borrowing capacity Line of Credit Facility, Potential Maximum Borrowing Capacity Line of Credit Facility, Potential Maximum Borrowing Capacity Amount outstanding under Letter of Credit Long-term Line of Credit Current borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Amount outstanding under the Credit Facility Line of Credit, Current Frequency of commitment fee payment Line of Credit Facility, Frequency of Commitment Fee Payment Principal amount Debt Instrument, Face Amount Debt convertible threshold trading days Debt Instrument, Convertible, Threshold Trading Days Debt convertible threshold consecutive trading days Debt Instrument, Convertible, Threshold Consecutive Trading Days Debt convertible maximum threshold percentage of stock price Debt Instrument, Convertible, Maximum Threshold Percentage of Stock Price Trigger Debt Instrument, Convertible, Maximum Threshold Percentage of Stock Price Trigger Debt convertible threshold percentage of stock price trigger Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger Current portion of long-term debt to be converted within 12 months Convertible Debt, Current Debt instrument, conversion ratio Debt Instrument, Convertible, Conversion Ratio Debt instrument conversion price per share Debt Instrument, Convertible, Conversion Price Senior note effective interest rate (in percent) Debt Instrument, Interest Rate, Effective Percentage Senior notes amortization period Debt Instrument, Convertible, Remaining Discount Amortization Period If-converted value in excess of principal on convertible debt Debt Instrument, Convertible, If-converted Value in Excess of Principal Amount of debt extinguished Extinguishment of Debt, Amount Proceeds from issuance of debt Proceeds from Issuance of Debt Shares issued in connection with exchange Debt Conversion, Converted Instrument, Shares Issued Shares issued for services render in connection with the 3.75% exchange Stock Issued During Period, Shares, Issued for Services Frequency of periodic payment Debt Instrument, Frequency of Periodic Payment Increase of interest rate contingent on principal amount outstanding Debt Instrument, Interest Rate Increase, Contingent on Principal Amount Outstanding Additional interest rate per year to be payable for any semiannual interest period for which principal amount outstanding on Notes is less than the required amount Minimum principal amount outstanding threshold for interest rate increase Debt Instrument, Interest Rate Increase, Minimum Principal Amount Outstanding Threshold Debt Instrument, Interest Rate Increase, Minimum Principal Amount Outstanding Threshold Debt redemption start date Debt Instrument, Redemption Period, Start Date Debt redemption price, percentage of principal amount Debt Instrument, Redemption Price, Percentage Convertible debt discount amortization period Debt Instrument, Convertible, Discount Amortization Period Debt Instrument, Convertible, Discount Amortization Period Convertible debt, carrying amount of equity component Debt Instrument, Convertible, Carrying Amount of Equity Component Repayments of debt amount Repayments of Debt Shares issued in connection with conversion Land Land [Member] Capitalized software Software and Software Development Costs [Member] Summary of property and equipment Property, Plant and Equipment, Net, by Type [Abstract] Property and equipment, gross Property, Plant and Equipment, Gross Less: accumulated depreciation and amortization on building and improvements, furniture and equipment Property, Plant, and Equipment, Owned, Accumulated Depreciation Less: accumulated amortization for capitalized software Capitalized Computer Software, Accumulated Amortization Accumulated depreciation, Total Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, equipment, and capitalized software, net Preliminary Values of Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Intangible ASsets Acquired Identified by Segment Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Significant components of deferred tax assets and liabilities Components of Deferred Tax Assets and Liabilities [Abstract] Accrued expenses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Reserve liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Reserves Other accrued medical costs Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits Net operating losses Deferred Tax Assets, Operating Loss Carryforwards Unrealized losses Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross Unearned premiums Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Unearned Premiums Reserve Lease financing obligation Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Deferred Rent Deferred compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation Tax credit carryover Deferred Tax Assets, Tax Credit Carryforwards Valuation allowance Total deferred income tax assets, net of valuation allowance Deferred Tax Assets, Net of Valuation Allowance Prepaid expenses Deferred Tax Liabilities, Prepaid Expenses Depreciation and amortization Deferred Tax Liabilities, Property, Plant and Equipment Basis in debt Deferred Tax Liabilities, Financing Arrangements Total deferred income tax liabilities Deferred Tax Liabilities, Gross Net deferred income tax asset - long term Deferred Tax Assets, Net Employee Stock Purchase Plan Employee Stock Purchase Plan [Member] Employee stock purchase plan. Employee purchase price as a percentage of stock price Fair Market Value Of Common Stock Percentage Fair market value of common stock, Percentage. Maximum annual contribution per employee Share Based Compensation Arrangement By Share Based Payment Award Maximum Amount Per Employee Share based compensation arrangement by share based payment award maximum amount per employee. Minimum expected volatility rate inputs for fair value measurement (in percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Maximum expected volatility rate inputs for fair value measurement (in percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Common stock issued during period (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Current assets Current Assets [Member] Current Assets [Member] Non-current assets Non-current assets [Member] Non-current assets Current liabilities Current Liabilities [Member] Current Liabilities [Member] Non-current liabilities Non-current liabilities [Member] Non-current liabilities [Member] Derivative asset Derivative Asset, Fair Value, Gross Asset Derivative liability Derivative Liability, Fair Value, Gross Liability Stock based compensation expense Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Restricted and performance stock activity Schedule of Nonvested Share Activity [Table Text Block] Fair Values of Derivative Financial Instruments Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Shares outstanding at the beginning of the period Weighted-average number of shares: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Common stock offering Weighted Average Number of Shares Issued, Basic Convertible senior notes Weighted Average Number of Shares Issued, Exchange of Debt Instruments Weighted Average Number of Shares Issued, Exchange of Debt Instruments Repurchased Weighted Average Number of Shares, Common Stock Subject to Repurchase or Cancellation Denominator for basic net income per share Effect of dilutive securities: Dilutive Securities, Effect on Basic Earnings Per Share [Abstract] Share-based compensation Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Convertible senior notes Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities 1.125% Warrants Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Denominator for diluted net income per share Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] 1.125% Warrants Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] 1.125% Warrants Cash Convertible Senior Notes Due 2020, Warrants [Member] Cash Convertible Senior Notes Due 2020, Warrants [Member] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Potentially dilutive common shares excluded from calculations Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Stated interest rate (as a percent) Class Of Warrant Or Right, Stated Interest Rate Class Of Warrant Or Right, Stated Interest Rate Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Variable Interest Entities [Axis] Variable Interest Entities [Axis] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] New Mexico Data Center New Mexico Data Center [Member] New Mexico data center. Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Variable interest entity, total assets Variable Interest Entity, Consolidated, Carrying Amount, Assets Variable interest entity, total liabilities Variable Interest Entity, Consolidated, Carrying Amount, Liabilities Tax credit claimed as a percentage of original investment amount Tax Credit Claimed As Percentage Of Original Investment Amount Tax credit claimed as percentage of original investment amount. Tax credit claimed, term Tax Credit Claimed, Term Tax Credit Claimed, Term Percentage of credit claimed for first three years Percentage of credit claimed for first three years Percentage of credit claimed for first three years. Percentage of credit claimed for remaining four years Percentage Of Credit Claimed For Each Of Remaining Four Years Percentage of credit claimed for each of remaining four years. Capital contribution by related party Capital Contribution by Related Party Capital contribution by related party. Principal amount of loan by party Principal Amount Of Loan By Party Principal amount of loan by party. Proceeds from other debt Proceeds from Other Debt Deferred finance costs, gross Deferred Finance Costs, Gross Percentage recapture for period of seven years as provided in Internal Revenue Code Percentage recapture for period of seven years as provided in Internal Revenue Code Percentage recapture for period of seven years as provided in Internal Revenue Code. Restricted stock and performance awards Restricted Stock Units With Performance Conditions [Member] Restricted stock units with performance conditions. Performance stock Performance Shares [Member] Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Unvested, shares beginning of period Granted Vested Forfeited Unvested, shares end of period Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Unvested, weighted average grant date fair value beginning balance (USD per share) Granted (USD 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 Vested (USD 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 Forfeited (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Unvested, weighted average grant date fair value ending balance (USD per share) Summary of quarterly results of operations Selected Quarterly Financial Information [Abstract] Service revenue Operating income Income from continuing operations Net income per share: Basic (USD per share) Diluted (USD per share) Interest cost recognized for the period relating to the: Interest Costs Incurred [Abstract] Contractual interest coupon rate Interest Expense, Debt, Excluding Amortization Amortization of the discount Amortization of Debt Discount (Premium) Total interest cost recognized Interest Expense, Debt Assets: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Prepaid expenses and other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Property and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Goodwill Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Liabilities: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Medical claims and benefits payable Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Liabilities, Medical Claims And Benefits Payable Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Liabilities, Medical Claims And Benefits Payable Accounts payable and accrued liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Deferred revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Other long-term liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other Total purchase price Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Fair Value Default [Member] Portion at Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Total Fair Value Estimate of Fair Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Estimated fair values of long-term debt Debt Instrument, Fair Value Disclosure Employee Benefits Compensation and Employee Benefit Plans [Text Block] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]