Name:	mgln_AvailableForSaleSecuritiesDebtMaturitiesInFollowingFullFiscalYearAmortizedCost
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Represents the debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments, if any, which are expected to mature in second full fiscal year following the balance sheet date and which are categorized neither as held-to-maturity nor as trading securities.

No definition available.

Name:	mgln_AvailableForSaleSecuritiesDebtMaturitiesInSecondYearAmortizedCost
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
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Represents the debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments, if any, which are expected to mature in third full fiscal year following the balance sheet date and which are categorized neither as held-to-maturity nor as trading securities.

No definition available.

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Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
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This item represents the fair value of debt securities, which are expected to mature within the next full fiscal year following the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

No definition available.

Name:	mgln_AvailableForSaleSecuritiesDebtMaturitiesWithinFollowingFullFiscalYearFairValue
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
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Represents the fair value of debt securities, which are expected to mature within second full fiscal year following the balance sheet date and which are categorized neither as held-to-maturity nor as trading securities.

No definition available.

Name:	mgln_AvailableForSaleSecuritiesDebtMaturitiesWithinSecondYearFairValue
Namespace Prefix:	mgln_
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Represents the fair value of debt securities, which are expected to mature within third full fiscal year following the balance sheet date and which are categorized neither as held-to-maturity nor as trading securities.

No definition available.

Name:	mgln_AvailableForSaleSecuritiesDebtMaturitiesWithinThirdYearFairValue
Namespace Prefix:	mgln_
Data Type:	xbrli:monetaryItemType
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of available-for-sale debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563