XML 110 R119.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Segmented Information - Schedule of Information with Respect to Segment (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Segment Reporting Information [Line Items] |  |  |
Total sales | $ 36,641 us-gaap_Revenues | $ 34,835 us-gaap_Revenues | $ 30,837 us-gaap_Revenues
Depreciation and amortization | 890 us-gaap_DepreciationDepletionAndAmortization | 1,063 us-gaap_DepreciationDepletionAndAmortization | 801 us-gaap_DepreciationDepletionAndAmortization
Adjusted EBIT | 2,632 mga_AdjustedEarningBeforeInterestAndTax | 2,065 mga_AdjustedEarningBeforeInterestAndTax | 1,658 mga_AdjustedEarningBeforeInterestAndTax
Goodwill | 1,350 us-gaap_Goodwill | 1,440 us-gaap_Goodwill | 1,473 us-gaap_Goodwill
Fixed assets, net | 5,664 us-gaap_PropertyPlantAndEquipmentNet | 5,441 us-gaap_PropertyPlantAndEquipmentNet |
Current assets | 10,007 us-gaap_AssetsCurrent | 9,923 us-gaap_AssetsCurrent | 9,135 us-gaap_AssetsCurrent
Investments, goodwill, deferred tax assets and other assets | 2,468 mga_InvestmentsGoodwillDeferredTaxAssetsAndOtherAssets | 2,626 mga_InvestmentsGoodwillDeferredTaxAssetsAndOtherAssets | 2,701 mga_InvestmentsGoodwillDeferredTaxAssetsAndOtherAssets
Consolidated total assets | 18,139 us-gaap_Assets | 17,990 us-gaap_Assets | 17,109 us-gaap_Assets
Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 36,641 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 34,835 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 30,837 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
External sales | 36,641 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 34,835 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 30,837 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Depreciation and amortization | 890 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,063 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 801 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Adjusted EBIT | 2,632 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 2,065 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,658 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Goodwill | 1,350 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,440 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,473 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Fixed asset additions | 1,587 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,170 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,274 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Fixed assets, net | 5,664 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 5,441 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 5,273 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
North America [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Goodwill | 635 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 656 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 701 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
North America [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 19,712 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 17,954 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 16,335 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
External sales | 19,603 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 17,859 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 16,241 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Depreciation and amortization | 421 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 598 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 432 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Adjusted EBIT | 1,992 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 1,645 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 1,521 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Goodwill | 635 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 656 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 701 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Fixed asset additions | 715 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 645 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 615 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
Fixed assets, net | 2,553 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 2,347 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember | 2,206 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember
North America [Member] | Intersubsegment Eliminations [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | (1,224)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember | (1,182)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember | (1,046)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember
North America [Member] | Canada [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 6,799 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 6,734 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 6,343 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 6,324 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 6,223 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 5,907 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 204 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 167 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 158 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 638 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 601 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 660 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_CanadaMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
North America [Member] | United States [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 9,780 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 8,409 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 7,518 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 9,252 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 7,938 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 7,053 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 351 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 349 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 294 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 1,260 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 1,135 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 973 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_UnitedStatesMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
North America [Member] | Mexico [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 4,357 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 3,993 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 3,520 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 4,027 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 3,698 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 3,281 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 160 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 129 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 163 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 655 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 611 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 573 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_NorthAmericaMember / us-gaap_SubsegmentsAxis = mga_MexicoMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Europe [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Goodwill | 588 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 655 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 611 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Europe [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 14,706 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 14,718 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 12,709 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
External sales | 14,494 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 14,525 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 12,563 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Depreciation and amortization | 357 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 355 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 283 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Adjusted EBIT | 434 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 375 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 165 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Goodwill | 588 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 655 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 611 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Fixed asset additions | 517 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 361 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 378 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Fixed assets, net | 2,012 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 2,169 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember | 2,132 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember
Europe [Member] | Intersubsegment Eliminations [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | (432)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember | (387)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember | (188)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_IntersubsegmentEliminationsMember
Europe [Member] | Western Europe Excluding Great Britain [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 11,775 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 11,813 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 10,089 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 11,487 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 11,544 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 9,927 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 375 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 225 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 246 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 1,359 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 1,463 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 1,490 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_WesternEuropeExcludingGreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Europe [Member] | Great Britain [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 783 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 975 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 961 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 781 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 968 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 952 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 51 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 24 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 15 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 98 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 70 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 58 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_GreatBritainMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Europe [Member] | Eastern Europe [Member] | Reportable Subsegments [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 2,580 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 2,317 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 1,847 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
External sales | 2,226 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 2,013 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 1,684 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed asset additions | 91 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 112 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 117 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Fixed assets, net | 555 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 636 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember | 584 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_EuropeMember / us-gaap_SubsegmentsAxis = mga_EasternEuropeMember / us-gaap_SubsegmentsConsolidationItemsAxis = us-gaap_ReportableSubsegmentsMember
Asia [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Goodwill | 127 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 129 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 74 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Asia [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 1,983 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 1,684 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 1,289 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
External sales | 1,837 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 1,539 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 1,188 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Depreciation and amortization | 71 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 64 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 42 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Adjusted EBIT | 162 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 85 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 49 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Goodwill | 127 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 129 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 74 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Fixed asset additions | 141 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 114 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 214 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Fixed assets, net | 650 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 597 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember | 558 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = us-gaap_AsiaMember
Rest of World [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Goodwill |  |  | 87 us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Rest of World [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 695 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 889 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 822 us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
External sales | 694 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 889 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 822 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Depreciation and amortization | 17 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 20 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 17 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Adjusted EBIT | (35)mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | (76)mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | (77)mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Goodwill |  |  | 87 us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Fixed asset additions | 8 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 20 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 56 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Fixed assets, net | 82 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 102 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember | 128 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementGeographicalAxis = mga_RestOfWorldMember
Corporate and Other [Member] | Operating Segments [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | (455)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (410)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (318)us-gaap_Revenues / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
External sales | 13 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 23 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 23 mga_ExternalSales / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Depreciation and amortization | 24 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 26 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 27 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Adjusted EBIT | 79 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 36 mga_AdjustedEarningBeforeInterestAndTax / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember |
Fixed asset additions | 206 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 30 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 11 us-gaap_PropertyPlantAndEquipmentAdditions / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Fixed assets, net | $ 367 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | $ 226 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | $ 249 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember

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Period Type: | duration

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Namespace Prefix: | mga_
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References 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 210.5-02.18) -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 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 + Details
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