Name:	mgln_DirectServiceCostsAndOtherOperatingExpenses
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The add back of the change in the fair value of contingent consideration, (excluding the portion that is recorded as interest expense) that is included in direct service costs and other operating expenses but is excluded from the computation of segment profit since it is managed on a consolidated basis..

No definition available.

Name:	mgln_ReconciliationOfSegmentProfitLossChangeInFairValueOfContingentConsiderationAddBack
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The add back of stock compensation expense that is included in direct service costs and other operating expenses but is excluded from the computation of segment profit since it is managed on a consolidated basis.

No definition available.

Name:	mgln_ReconciliationOfSegmentProfitLossShareBasedCompensationExpenseAddback
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Non-GAAP measure representing aggregate segment revenue less cost of goods and services, other operating and non-operating expenses, and non-controlling interest.

No definition available.

Name:	mgln_SegmentProfitLoss
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Name:	us-gaap_CostOfGoodsAndServicesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Total costs of health care costs, net of recoveries of stop-loss insurance. Costs of services rendered (including costs of services rendered but not yet reported).

No definition available.

Name:	us-gaap_HealthCareOrganizationExpensesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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

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.

No definition available.

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

Name:	srt_ProductOrServiceAxis=mgln_ManagedCareAndOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_ProductOrServiceAxis=mgln_PharmacyBenefitManagementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: