XML 128 R120.htm IDEA: XBRL DOCUMENT v2.4.1.9

Segmented Information - Schedule of Information with Respect to Segment (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Equity loss	$ 211us-gaap_IncomeLossFromEquityMethodInvestments	$ 196us-gaap_IncomeLossFromEquityMethodInvestments	$ 151us-gaap_IncomeLossFromEquityMethodInvestments
Adjusted EBIT	2,632mga_AdjustedEarningBeforeInterestAndTax	2,065mga_AdjustedEarningBeforeInterestAndTax	1,658mga_AdjustedEarningBeforeInterestAndTax
Other (expense) income, net	(64)us-gaap_OtherNonoperatingIncomeExpense	(144)us-gaap_OtherNonoperatingIncomeExpense	108us-gaap_OtherNonoperatingIncomeExpense
Interest expense, net	(29)us-gaap_InterestIncomeExpenseNonoperatingNet	(16)us-gaap_InterestIncomeExpenseNonoperatingNet	(16)us-gaap_InterestIncomeExpenseNonoperatingNet
Income from operations before income taxes	2,539us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1,905us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1,750us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Operating Segments [Member]
Segment Reporting Information [Line Items]
Adjusted EBIT	2,632mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember	2,065mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember	1,658mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Operating Segments [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Adjusted EBIT	79mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember	36mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Operating Segments [Member] | Corporate and Other [Member] | E-Car [Member]
Segment Reporting Information [Line Items]
Equity loss			$ 35us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_BusinessAcquisitionAxis = mga_ECarMember / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember

X

- Definition

Adjusted earning before interest and tax.

+ References

No definition available.

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X

- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35710027&loc=d3e41242-110953



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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X

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ 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 SEC

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-Number 210

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

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-Section 45

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-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.12)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688



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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 7

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- Definition

The net amount of nonoperating interest income (expense).

+ References

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.9)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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