Represents the notice period required for termination of contract.

No definition available.

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

- Definition

Represents the term of the contract entered with the customer.

+ References

No definition available.

+ Details

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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

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

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Data Type:	xbrli:stringItemType
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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=mgln_CentersForMedicareAndMedicaidServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=mgln_GeographicConcentrationRiskAreaOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_GovernmentContractsConcentrationRiskMember
Namespace Prefix:
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General - Concentration of Business (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Concentration of Business
Net revenue	$ 1,419,406	$ 1,292,132	$ 4,144,168	$ 3,573,499
Minimum
Concentration of Business
Term of Contract			1 year
Term of renewed contract			1 year
Notice period for termination of contract			60 days
Maximum
Concentration of Business
Term of Contract			3 years
Term of renewed contract			2 years
Notice period for termination of contract			180 days
CMS
Concentration of Business
Net revenue			$ 368,200	192,000
Pennsylvania Counties
Concentration of Business
Net revenue			357,300	343,200
Agencies and departments of the United States federal government
Concentration of Business
Net revenue			$ 257,700	$ 164,300