Document and Entity Information [Abstract] Document Information [Table] Legal Entity [Axis] Entity [Domain] Represents the Retirement Plan Number 002. E B P 002 [Member] The Magna Group of Companies Retirement Savings Plans Document Information [Line Items] Document Type Document Period End Date Entity Registrant Name Entity Central Index Key Amendment Flag Statements of Net Assets Available for Benefits EBP, Statement of Net Asset Available for Benefit [Table] EBP, Statement of Net Asset Available for Benefit [Line Items] EBP, Asset [Abstract] Assets EBP, Investment, Fair Value [Abstract] Investments Fair value of investments, excluding plan interest in master trust, held by an employee stock purchase, savings, or similar employee benefit plan (EBP), excluding investments measured at net asset value (NAV) per share as a practical expedient. EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Excluding Net Asset Value Investments, at fair value Net asset value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Investment, Excluding Plan Interest in Master Trust, Net Asset Value Investments, at net asset value EBP, Investment, Excluding Plan Interest in Master Trust, Contract Value Investments, at contract value EBP, Investment, Excluding Plan Interest in Master Trust, Fair and Contract Value Total Investments EBP, Receivable [Abstract] Receivables EBP, Employer Contribution, Receivable Employer EBP, Participant Contribution, Receivable Participants EBP, Note Receivable from Participant Notes receivable from participants EBP, Receivable Total Receivables EBP, Net Asset Available for Benefit Net Assets Available for Benefits, end of year Net Assets Available for Benefits, beginning of year Net Assets Available for Benefits Statements of Changes in Net Assets Available for Benefits EBP, Statement of Change in Net Asset Available for Benefit [Table] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Change in Net Asset Available for Benefit, Increase (Decrease) [Abstract] Changes in Net Assets Available for Benefits Changes in net assets available for benefits EBP, Change in Net Asset Available for Benefit, Increase [Abstract] Additions EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment [Abstract] Investment income: EBP, Change in Net Asset Available for Benefit, Increase from Interest and Dividend Income on Investment Interest and dividends EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment Net appreciation in fair value of investments Net appreciation/(depreciation) in fair value of investments EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] Contributions: EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash and Noncash Employer Employer contributions EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover Participants EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Rollovers EBP, Change in Net Asset Available for Benefit, Increase from Interest Income on Note Receivable from Participant Interest from notes receivable from participants EBP, Change in Net Asset Available for Benefit, Increase Total Additions EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Deductions Amount of decrease in net asset available for benefit from payment of benefit to terminated employees in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, withdrawal. Employee Benefit Plan, Change in Net Asset Available for Benefit, Decrease from Payment to Terminated Employees Distributions to terminated employees Benefits paid to terminated employees EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Distributions to participating employees Benefits paid to participating employees EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Loan expenses and other fees EBP, Change in Net Asset Available for Benefit, Decrease Total Deductions EBP, Change in Net Asset Available for Benefit, Increase (Decrease) Net increase Amount of net asset available for benefit transferred from employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from external plan. EBP, Change in Net Asset Available for Benefit, Transfer from Plan Transfers from other plans Description of the Plan EBP, Description of Plan [Table] EBP, Description of Plan [Line Items] Description of the Plan EBP, Description of Plan [Text Block] Description of the Plan Significant Accounting Policies EBP, Accounting Policy [Table] EBP, Accounting Policy [Line Items] Significant Accounting Policies EBP, Summary of Accounting Policy [Text Block] Significant Accounting Policies Investments EBP, Investment, Fair Value and NAV [Table] EBP, Investment, Fair Value and NAV [Line Items] Investments EBP, Investment, Fair Value and NAV [Text Block] Investments Non-Participant-Directed Investments EBP, Nonparticipant-Directed Investment [Table] EBP, Nonparticipant-Directed Investment [Line Items] Non-Participant-Directed Investments EBP, Nonparticipant-Directed Investment [Text Block] Non-Participant-Directed Investments Related Party and Party-In-Interest Transactions EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Line Items] Related Party and Party-In-Interest Transactions EBP, Related Party and Party-in-Interest Transactions [Text Block] Related Party and Party-In-Interest Transactions Income Tax Status EBP, Tax Status [Table] EBP, Tax Status [Line Items] Income Tax Status EBP, Tax Status [Text Block] Income Tax Status No definition available. Delinquent Participant Contributions EBP, Schedule of Delinquent Participant Contribution [Table] EBP, Schedule of Delinquent Participant Contribution [Line Items] Delinquent Participant Contributions Schedule H, Line 4a - Schedule of Delinquent Participant Contributions The entire disclosure for delinquent participant contribution for employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Delinquent Participant Contribution [Text Block] Delinquent Participant Contributions Commitments and Contingencies EBP, Contingency [Table] EBP, Contingency [Line Items] Commitments and Contingencies EBP, Contingency [Text Block] Commitments and Contingencies Schedule H, Line 4a - Schedule of Delinquent Participant Contributions EBP, Schedule of Delinquent Participant Contribution [Text Block] Schedule H, Line 4a - Schedule of Delinquent Participant Contributions Schedule H, Line 4i - Schedule of Assets (Held at End of Year) EBP, Schedule of Asset Held for Investment [Table] EBP, Schedule of Asset Held for Investment [Line Items] Schedule H, Line 4i - Schedule of Assets (Held at End of Year) EBP, Schedule of Asset Held for Investment [Table Text Block] Schedule H, Line 4i - Schedule of Assets (Held at End of Year) EBP, Basis of Accounting [Policy Text Block] Basis of Financial Statements EBP, Subsequent Event [Policy Text Block] Subsequent Events EBP, Use of Estimate [Policy Text Block] Use of Estimates EBP, Risk and Uncertainty [Policy Text Block] Risks and Uncertainties EBP, Investment [Policy Text Block] Investment Valuation and Income Recognition EBP, Contribution [Policy Text Block] Contributions EBP, Note Receivable from Participant [Policy Text Block] Notes Receivable from Participants Disclosure of accounting policy for concentration of investments. Employee Benefit Plan, Concentration of Investments [Policy Text Block] Concentration of Investments EBP, Payment to Participant [Policy Text Block] Payment of Benefits The tabular disclosure of years of vesting service and vested percentage. Employee Benefit Plan, Vesting Service Period and Vested Percentage [Table Text Block] Schedule of vesting for the historical deferred profit-sharing portion of the plan EBP, Investment, Fair Value and NAV [Table Text Block] Schedule of fair value hierarchy of investments The tabular disclosure of level 3 reconciliation of fair value of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Investment, Level 3 Reconciliation [Table Text Block] Schedule of summary of changes in the fair values of the Level 3 investments EBP, Nonparticipant-Directed Investment [Table Text Block] Schedule of net assets available for benefits and the significant components of the changes in net assets available for benefits for non-participant-directed investments Statistical Measurement [Axis] Statistical Measurement [Domain] Minimum [Member] Minimum Maximum [Member] Maximum EBP, Description, Available [true false] Description of plan available Represents the minimum service period for plan eligibility under (employee benefit plan (EBP)). Employee Benefit Plan, Minimum Service Period For Plan Eligibility Minimum service period for Plan eligibility Represents the minimum age criteria for plan eligibility under (employee benefit plan (EBP)). Employee Benefit Plan, Minimum Age For Plan Eligibility Minimum age for Plan eligibility Represents the service period expressed in hours, for profit sharing eligibility under (employee benefit plan (EBP)). Employee Benefit Plan, Service Period for Profit Sharing Eligibility, Hours Service period for profit sharing eligibility (in hours) Percentage of minimum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation. Employee Benefit Plan, Participant Contribution, Pretax, Minimum Annual Compensation to Total Compensation Percentage Minimum amount of compensation eligible for participant contribution (as a percent) Percentage of pretax annual compensation that new hires are automatically enrolled to contribute to total pretax annual compensation in employee stock purchase, saving, or similar plan (employee benefit plan (EBP). Employee Benefit Plan, Participant Contribution, New Hires, Automatic Enrollment, Annual Compensation to Total Compensation, Percentage Percentage of automatic enrollment for newly hires Percentage of pretax annual compensation that new hires, who are covered by certain collective bargaining agreements, are automatically enrolled to contribute to total pretax annual compensation in employee stock purchase, saving, or similar plan (employee benefit plan (EBP). Employee Benefit Plan, Participant Contribution, New Hires Covered By Collective Bargaining Agreements, Automatic Enrollment, Annual Compensation to Total Compensation, Percentage Percentage of automatic enrollment for newly hires covered under certain bargaining agreements EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage Maximum amount of compensation eligible for participant contribution (as a percent) EBP, Employer Contribution, Matching Percentage Employer matching contribution (as a percent) EBP, Employer Contribution, Participant Compensation Matched, Percentage Participant compensation matched (as a percent) Percentage of pretax annual bonus that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation. Employee Benefit Plan, Participant Contribution, Pretax, Annual Bonus to Total Compensation, Percentage Participant's annual bonus deferral rate (as a percent) Represents the enrollment opt out period under (employee benefit plan (EBP)). Employee Benefit Plan, Enrollment, Opt Out Period Opt out period Percentage of automatic increase per year in pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), contributes to total pretax annual compensation. Employee Benefit Plan, Participant Contribution, Automatic Increase Per Year, Percent Employee contribution automatic increase per year (as a percent) Percentage of contribution after increase in pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), contributes to total pretax annual compensation. Employee Benefit Plan, Maximum Contribution after Automatic Increase, Percent Employee contribution after automatic increase (as a percent) Threshold percent of contribution for increase in pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), contributes to total pretax annual compensation. Employee Benefit Plan, Maximum Contribution for Automatic Increase, Threshold Percent Employee contribution automatic increase, threshold (as a percent) Percentage of employer base contribution for each eligible participant determined by multiplying with their applicable regular earnings. Employee Benefit Plan, Employer Base Contribution, Participant Regular Earnings, Percent Magna Base Contribution (as a percent) Represents the minimum service period for plan eligibility under base contribution plan. Employee Benefit Plan, Employer Base Contribution, Minimum Service Period For Plan Eligibility Magna Base Contribution, service period Represents the minimum age criteria for plan eligibility under base contribution plan. Employee Benefit Plan, Employer Base Contribution, Minimum Age For Plan Eligibility Magna Base Contribution, minimum age for eligibility Information by years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service [Axis] Employee Benefit Plan, Years of Vesting Service [Axis] Years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service [Domain] Employee Benefit Plan, Years of Vesting Service [Domain] Tranche one of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche One [Member] Less than 1 year Tranche two of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche Two [Member] 1 years Tranche three of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche Three [Member] 2 years Tranche four of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche Four [Member] 3 years Tranche five of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche Five [Member] 4 years Tranche six of years of vesting service in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Years of Vesting Service, Tranche Six [Member] 5 years and after Retirement Plan Type [Axis] Retirement Plan Type [Domain] Information on entity -sponsored retirement savings account that allows employees to contribute a portion of their paycheck, often pre-tax, to invest for retirement. Plan, 401 K [Member] 401 (k) Deferred Profit Sharing [Member] Deferred Profit - Sharing Represents the percentage of vesting. Employee Benefit Plan, Vesting Percentage Vesting percentage Represents the maximum vesting period for allocated or re-allocated investments under employee benefit plan. Employee Benefit Plan, Allocated or Reallocated Investments, Maximum Vesting Period Vesting period for allocated or re-allocated amounts Represents the retirement age for immediate full vesting under employee benefit plan. Employee Benefit Plan, Retirement Age for Immediate Full Vesting Retirement age for immediate full vesting Represents the number of consecutive one-year breaks in service for forfeiture in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Number of Consecutive One-year Breaks in Service for Forfeiture Number of consecutive one-year breaks in service for forfeiture Represents the period of breaks in service for forfeiture in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Forfeited Nonvested Account, Service Break Period Service break period EBP, Forfeited Nonvested Account, Reallocated to Participant Allocated forfeitures EBP, Forfeited Nonvested Account Forfeited nonvested accounts Represents the number of continuous years of service for vested benefits distribution under employee benefit plan. Employee Benefit Plan, Vested Benefits Distribution, Period of Continuous Years of Service Continuous years of service for vested benefits distribution Represents the age of participant for vested benefits distribution under employee benefit plan. Employee Benefit Plan, Participant Age for Vested Benefits Distribution Participant age for distribution of vested benefits EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount Minimum amount that participant may borrow EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount Maximum amount that participant may borrow EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage Maximum vested account balance for loans (as a percent) Represents the term of participant loan Employee Benefit Plan, Note Receivable From Participant, Term Participant loan term Represents the maximum term of loan if proceeds are used for the purchase of principal residence. Employee Benefit Plan, Note Receivable From Participant Maximum Term if Proceeds Used to Purchase Primary Residence Maximum loan term if proceeds are used for the purchase of principal residence Represents the percentage points added to the prime rate to compute the interest rate on participant loans. Employee Benefit Plan, Note Receivable From Participant, Basis Spread on Prime Rate Basis spread on prime rate (as a percent) EBP, Asset Held for Investment, Participant Loan, Interest Rate Interest on loans (as a percent) Represents the percentage of vesting of participant accounts in the event of plan termination. Employee Benefit Plan, Vesting Percentage in Event of Plan Termination Vesting percentage in the event of plan termination EBP, Participant-Directed and Nonparticipant-Directed Status [Axis] EBP, Participant-Directed and Nonparticipant-Directed Status [Domain] EBP, Nonparticipant-Directed [Member] Non-participant directed Investment Type [Axis] Investments [Domain] EBP, Employer, Common Stock [Member] Employer's securities Represents the percentage of deferred profit sharing, invested in employer securities under employee benefit plan. Employee Benefit Plan, Percent of Deferred Profit Sharing Invested in Employer Securities Deferred profit sharing (as a percent) Represents the maximum diversification percent of employer securities by participant. Employee Benefit Plan, Employer Securities, Maximum Diversification Percent Maximum diversification percent Amount of net asset available for benefit transferred to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) to external plan. EBP, Change in Net Asset Available for Benefit, Transfer to Plan Net assets transferred to plan EBP, Risk and Uncertainty, Concentration of Investment at Fair Value to Total Investments, Amount Concentration of investment to total investments EBP, Risk and Uncertainty, Concentration of Investment at Fair Value to Total Investments, Percentage Concentration of investment to total investments (as a percent) Represents information pertaining to stable Value Fund. Employee Benefit Plan, Stable Value Fund [Member] Stable Value Fund EBP, Pooled Separate Account [Member] Pooled Separate Accounts Common Collective Trust [Member] Common/Collective Trusts Represents the number of days of prohibition to move back into fund after liquidation. Employee Benefit Plan, Investment, Prohibition Period for Moving Back into Fund after Liquidation Number of days of prohibition to move back into fund Represents the period of delay for withdrawal or transfer requests due to contractual limitation. Employee Benefit Plan, Investment, Maximum Delay for Withdrawal or Transfer Requests Period of delay for withdrawal or transfer requests Represents the period of transferring investments. Employee Benefit Plan, Investment, Transfer Period Investment transfer period EBP, Fair Value, Investment, NAV, Unfunded Commitment Unfunded commitments Guaranteed return of fully benefit-responsive investment contract held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). EBP, Fully Benefit-Responsive Investment Contract, Guaranteed Return Guaranteed return Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Level 1,2 &3 Fair Value, Inputs, Level 1 [Member] Level 1 Fair Value, Inputs, Level 3 [Member] Level 3 Fair Value Measured at Net Asset Value Per Share [Member] Net asset value Mutual Fund [Member] Mutual funds Represents information pertaining to deferred income annuities. Employee Benefit Plan, Deferred Income Annuities [Member] Deferred income annuities Deferred Income Annuities Represents information pertaining to life insurance policies. Employee Benefit Plan, Life Insurance Policies [Member] Life insurance policies EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Balance, end of year Balance, beginning of year Investments, at fair value Magna International Inc. common stock EBP, Investment, Level 3 Reconciliation [Roll Forward] Changes in the fair values of the Plan's Level 3 investments EBP, Investment, Level 3 Reconciliation, Increase from Purchase Purchases EBP, Investment, Level 3 Reconciliation, Decrease from Sale Sales EBP, Net Asset Available for Benefit [Abstract] Net assets available for benefits EBP, Change in Net Asset Available for Benefit, Increase from Dividend Income on Investment Dividend income EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution Participant contributions Amount of decrease in net asset available for benefit from inter fund transfers in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, withdrawal. Employee Benefit Plan, Change in Net Asset Available for Benefit, Decrease from Inter Fund Transfers Net inter-fund transfers EBP, Related Party and Party-in-Interest [Axis] EBP, Related Party and Party-in-Interest [Domain] EBP, Related Party and Party-in-Interest [Domain] Employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Employee Benefit Plan, Employer [Member] Employer EBP, Investment Acquired, Excluding Plan Interest in Master Trust, Cost Purchases EBP, Investment Sold, Excluding Plan Interest in Master Trust, Selling Price Sales EBP, Tax Determination Letter, Obtained [true false] Determination letter obtained EBP, Tax Determination Letter, Date Determination letter date EBP, Tax Qualification Status [Extensible Enumeration] Tax qualification status EBP, Schedule of Delinquent Participant Contribution, Transferred Late to Plan Amount failed to remit to plan in a timely manner Entity Tax Identification Number Entity tax identification number EBP, Plan Number Plan number EBP, Schedule of Delinquent Participant Contribution, Late Repayment Included [true false] Late participant loan repayments included EBP, Schedule of Delinquent Participant Contribution, Corrected Outside VFCP Contributions Corrected Outside VFCP