General (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Concentration of Business
Net revenue	$ 821,761	$ 773,213
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
Pennsylvania Counties
Concentration of Business
Net revenue	86,700	92,300
Florida Areas
Concentration of Business
Net revenue	$ 33,300	$ 34,100

Represents the notice period required for termination of contract.

No definition available.

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- Definition

Represents the term of the contract entered with the customer.

+ References

No definition available.

+ Details

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- 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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- Details

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ 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=6880815&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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