XML 58 R45.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Investments - Available-for-Sale Investments (Details) $ in Millions | Mar. 31, 2018 USD ($) Security | Dec. 31, 2017 USD ($) Security
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 2,001 | $ 1,940
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 11 | $ 5
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 915 | 719
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 226 | $ 227
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 4 | $ 3
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 164 | 164
Corporate debt securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 1,276 | $ 1,297
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 7 | $ 3
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 610 | 561
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 93 | $ 94
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 2 | $ 1
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 71 | 69
U.S. treasury notes |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 364 | $ 470
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 1 | $ 1
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 81 | 89
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 0 | $ 0
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 0 | $ 0
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 0 | 0
GSEs |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 179 | $ 173
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 1 | $ 1
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 67 | 69
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 95 | $ 95
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 1 | $ 1
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 47 | 47
Municipal securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 85 | $ 0
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 1 | $ 0
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 97 | 0
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 38 | $ 38
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 1 | $ 1
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 46 | 48
Asset-backed securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In a Continuous Loss Position for Less than 12 Months, Estimated Fair Value | $ 97 |
In a Continuous Loss Position for Less than 12 Months, Unrealized Losses | $ 1 |
In a Continuous Loss Position for Less than 12 Months, Number of Positions (in security) | Security | 60 |
In a Continuous Loss Position for 12 Months or More, Estimated Fair value | $ 0 |
In a Continuous Loss Position for 12 Months or More, Unrealized Losses | $ 0 |
In a Continuous Loss Position for 12 Months or More, Number of Positions (in security) | Security | 0 |

X
- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
Name: | us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

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

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

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

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