XML 150 R69.htm IDEA: XBRL DOCUMENT v2.4.1.9

Goodwill - Goodwill by Segment (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, Beginning balance	$ 1,440us-gaap_Goodwill	$ 1,473us-gaap_Goodwill
Acquisitions	3us-gaap_GoodwillAcquiredDuringPeriod	1us-gaap_GoodwillAcquiredDuringPeriod
Impairments		(22)us-gaap_GoodwillImpairmentLoss
Foreign exchange and other	(93)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments	(12)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments
Goodwill, Ending balance	1,350us-gaap_Goodwill	1,440us-gaap_Goodwill
North America [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	656us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember	701us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Acquisitions	3us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember	(24)us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Foreign exchange and other	(24)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember	(21)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Goodwill, Ending balance	635us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember	656us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Europe [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	655us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember	611us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Acquisitions		22us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Foreign exchange and other	(67)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember	22us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Goodwill, Ending balance	588us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember	655us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Asia [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	129us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember	74us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Acquisitions		3us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Reallocation between reporting segments		51us-gaap_GoodwillTransfers / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Foreign exchange and other	(2)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember	1us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Goodwill, Ending balance	127us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember	129us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Rest of World [Member]
Goodwill [Line Items]
Goodwill, Beginning balance		87us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Impairments		(22)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Reallocation between reporting segments		(51)us-gaap_GoodwillTransfers / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Foreign exchange and other		$ (14)us-gaap_GoodwillTranslationAndPurchaseAccountingAdjustments / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember

X

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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X

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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X

- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of transfers of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized among segments.

+ References

No definition available.

+ Details

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X

- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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