XML 110 R62.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Investments - Schedule of Investments (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Investments |  |
Amortized Cost | $ 1,692 | $ 2,700
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | 11 | 8
Estimated Fair Value | 1,681 | 2,693
U.S. Treasury notes |  |
Investments |  |
Amortized Cost |  | 68
Gross Unrealized Gains |  | 0
Gross Unrealized Losses |  | 0
Estimated Fair Value |  | 68
Corporate debt securities |  |
Investments |  |
Amortized Cost |  | 101
Gross Unrealized Gains |  | 0
Gross Unrealized Losses |  | 0
Estimated Fair Value |  | 101
Subtotal - current restricted investments |  |
Investments |  |
Amortized Cost |  | 169
Gross Unrealized Gains |  | 0
Gross Unrealized Losses |  | 0
Estimated Fair Value |  | 169
Corporate debt securities |  |
Investments |  |
Amortized Cost | 1,131 | 1,591
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | 8 | 4
Estimated Fair Value | 1,123 | 1,588
U.S. Treasury notes |  |
Investments |  |
Amortized Cost | 181 | 389
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 1
Estimated Fair Value | 181 | 388
GSEs |  |
Investments |  |
Amortized Cost | 164 | 255
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 1 | 2
Estimated Fair Value | 163 | 253
Municipal securities |  |
Investments |  |
Amortized Cost | 115 | 142
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 1 | 1
Estimated Fair Value | 114 | 141
Asset-backed securities |  |
Investments |  |
Amortized Cost | 83 | 117
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 1 | 0
Estimated Fair Value | 82 | 117
Certificates of deposit |  |
Investments |  |
Amortized Cost | 14 | 37
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Estimated Fair Value | 14 | 37
Other |  |
Investments |  |
Amortized Cost | 4 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | 0 |
Estimated Fair Value | $ 4 |
Subtotal - current investments |  |
Investments |  |
Amortized Cost |  | 2,531
Gross Unrealized Gains |  | 1
Gross Unrealized Losses |  | 8
Estimated Fair Value |  | $ 2,524

X
- Definition Schedule of available for sale securities reconciliation. + References No definition available. + Details
Name: | moh_ScheduleOfAvailableForSaleSecuritiesReconciliationAbstract
Namespace Prefix: | moh_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis=moh_RestrictedInvestmentsCurrentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryNotesSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=moh_MunicipalSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=moh_OtherFinancialInstrumentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=moh_CurrentInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |