Number of members eligible for the health care programs.

No definition available.

Name:	moh_BusinessCombinationNumberOfMembersEligibleForTheHealthCarePrograms
Namespace Prefix:	moh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Health Plan, Contract Term

+ References

No definition available.

+ Details

Name:	moh_HealthPlanContractTerm
Namespace Prefix:	moh_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of Members Covered

+ References

No definition available.

+ Details

Name:	moh_NumberOfMembersCovered
Namespace Prefix:	moh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number Of States With Government-Sponsored Healthcare Programs

+ References

No definition available.

+ Details

Name:	moh_NumberOfStatesWithGovernmentSponsoredHealthcarePrograms
Namespace Prefix:	moh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

+ Details

Name:	us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(1))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column E))
-URI http://asc.fasb.org/extlink&oid=120401096&loc=d3e574992-122915

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(c))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

+ Details

Name:	us-gaap_PremiumsEarnedNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=moh_CignaCorporationsTexasMedicaidAndMedicareMedicaidPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=moh_HidalgoTarrantAndNortheastServiceAreasMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=moh_HidalgoServiceAreaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=moh_CignaCorporationsTexasMedicaidAndMedicareMedicaidPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=moh_AffinityHealthPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=moh_HealthPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Organization and Basis of Presentation (Details) member in Thousands, $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Apr. 22, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) position member	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) position member	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) member
Segment Reporting Information [Line Items]
Number of states with programs \| position			18		18
Premium revenue			$ 6,583	$ 4,372	$ 12,889	$ 8,676
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan
Segment Reporting Information [Line Items]
Premium revenue							$ 1,000
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan \| Hidalgo, Tarrant and Northeast Service Areas
Segment Reporting Information [Line Items]
Number of members covered \| member							48
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan \| Hidalgo Service Area
Segment Reporting Information [Line Items]
Number of members covered \| member							2
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan
Segment Reporting Information [Line Items]
Total Purchase price	$ 60
Affinity health plan
Segment Reporting Information [Line Items]
Net cash paid in business combinations		$ 380
Health Plans
Segment Reporting Information [Line Items]
Number of members eligible for the health care programs, approximately \| member			4,700		4,700
Minimum \| Health Plans
Segment Reporting Information [Line Items]
Contract term					3 years
Maximum \| Health Plans
Segment Reporting Information [Line Items]
Contract term					5 years