The number of times a contract may be renewed under a contract agreement.

No definition available.

Name:	mgln_NumberOfContractRenewals
Namespace Prefix:	mgln_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the term of the contract entered with the customer.

+ References

No definition available.

+ Details

Name:	mgln_TermOfContract
Namespace Prefix:	mgln_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the term of the renewed contract with the customer.

+ References

No definition available.

+ Details

Name:	mgln_TermOfRenewedContract
Namespace Prefix:	mgln_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of days required for a customer to have the right to terminate a contract for cause.

+ References

No definition available.

+ Details

Name:	mgln_TerminationClauseNumberOfDaysNoticeToTerminate
Namespace Prefix:	mgln_
Data Type:	xbrli:durationItemType
Balance Type:	na
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_EntityWideRevenueMajorCustomerLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

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

+ Details

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

- 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:

- Details

Name:	srt_MajorCustomersAxis=mgln_VirginiaContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_CccPlusContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_MedallionContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_NewYorkContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_MassachusettsContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_SCOContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=mgln_CmsContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	srt_MajorCustomersAxis=mgln_CustomerAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	srt_MajorCustomersAxis=mgln_CustomerBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

General - Customers Exceeding Ten Percent of Consolidated Net Revenues (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) item	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) item	Jun. 30, 2018 USD ($)
Operating results by business segment
Revenues	$ 1,788,336	$ 1,810,923	$ 3,527,825	$ 3,616,000
Minimum
Operating results by business segment
Term of contracts with customers			1 year
Term of contract extensions or renewals			1 year
Maximum
Operating results by business segment
Term of contracts with customers			3 years
Term of contract extensions or renewals			2 years
Virginia Contracts
Operating results by business segment
Revenues			$ 391,200	228,800
CCC Plus Contract
Operating results by business segment
Term of contracts with customers			5 years
Term of contract extensions or renewals			12 months
Termination notice			90 days
CCC Plus Contract \| Maximum
Operating results by business segment
Number of contract extensions or renewals \| item	5		5
Medallion Contract
Operating results by business segment
Number of contract extensions or renewals \| item	6		6
Term of contract extensions or renewals			12 months
Termination notice			180 days
New York Contract
Operating results by business segment
Revenues			$ 400,600	356,600
Massachusetts Contracts
Operating results by business segment
Revenues			$ 360,900	330,900
SCO Contract
Operating results by business segment
Term of contract extensions or renewals			1 year
Termination notice			180 days
SCO Contract \| Maximum
Operating results by business segment
Number of contract extensions or renewals \| item	5		5
CMS Contract
Operating results by business segment
Term of contracts with customers			1 year
Healthcare
Operating results by business segment
Revenues	$ 1,220,642		$ 2,384,895
Healthcare \| Customer A
Operating results by business segment
Revenues			118,061	307,902
Pharmacy Management
Operating results by business segment
Revenues	$ 612,658		1,229,118
Pharmacy Management \| Customer B
Operating results by business segment
Revenues			$ 174,535	$ 176,650