XML 38 R104.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Stock-Based Compensation - Schedule of Restricted Stock Unit Programs Outstanding (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Equity Classified RSUs [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options outstanding, Beginning Balance | 631,854 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 605,430 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 367,726 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember
Granted | 181,526 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 224,841 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 320,131 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember
Dividend equivalents | 839 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 1,262 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 1,895 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember
Redeemed | (321,580)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | (199,679)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | (84,322)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember
Number of options outstanding, Ending Balance | 492,639 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 631,854 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember | 605,430 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_EquityClassifiedRestrictedStockUnitsMember
Liability Classified RSUs [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options outstanding, Beginning Balance | 30,119 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 20,099 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 29,806 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember
Granted | 9,025 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 13,825 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 15,364 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember
Dividend equivalents | 566 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 624 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 1,133 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember
Forfeitures | (410)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember |  |
Redeemed | (16,274)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | (4,429)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | (26,204)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember
Number of options outstanding, Ending Balance | 23,026 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 30,119 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember | 20,099 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityClassifiedRestrictedStockUnitsMember
Liability/Equity Classified DSUs [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options outstanding, Beginning Balance | 127,447 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 206,923 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 198,446 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Granted | 22,136 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 30,716 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 37,456 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Dividend equivalents | 2,047 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 2,815 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 5,145 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Redeemed |  | (113,007)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | (34,124)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Number of options outstanding, Ending Balance | 151,630 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 127,447 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember | 206,923 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Release of Restricted Stock Units [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options outstanding, Beginning Balance | 789,420 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 832,452 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 595,978 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember
Granted | 212,687 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 269,382 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 372,951 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember
Dividend equivalents | 3,452 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 4,701 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 8,173 mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember
Forfeitures | (410)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember |  |
Redeemed | (337,854)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | (317,115)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | (144,650)mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember
Number of options outstanding, Ending Balance | 667,295 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 789,420 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember | 832,452 us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember

X
- Definition Share based compensation arrangement by share based payment award equity instruments other than options dividend equivalents in period. + References No definition available. + Details
Name: | mga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsDividendEquivalentsInPeriod
Namespace Prefix: | mga_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share based compensation arrangement by share based payment award equity instruments other than options redeemed in period. + References No definition available. + Details
Name: | mga_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsRedeemedInPeriod
Namespace Prefix: | mga_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=mga_EquityClassifiedRestrictedStockUnitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=mga_LiabilityClassifiedRestrictedStockUnitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=mga_LiabilityEquityClassifiedDirectorShareBasedCompensationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |