Represents the notice period required for termination of contract.

No definition available.

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Namespace Prefix:	mgln_
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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_
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Period Type:	duration

- Definition

Represents the term of the renewed contract with the customer.

+ References

No definition available.

+ Details

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Namespace Prefix:	mgln_
Data Type:	xbrli:durationItemType
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- 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:
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Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

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Namespace Prefix:
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General - Concentration of Business (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Concentration of Business
Net revenue	$ 1,419,139	$ 1,164,345	$ 2,724,762	$ 2,281,367
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			$ 236,100	115,500
Pennsylvania Counties
Concentration of Business
Net revenue			232,400	226,000
Agencies and departments of the United States federal government
Concentration of Business
Net revenue			$ 177,500	$ 82,500