Proceeds From Other Investment.

No definition available.

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Namespace Prefix:	mga_
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Balance Type:	credit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

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Debt - Additional Information (Detail)			3 Months Ended	12 Months Ended
Debt - Additional Information (Detail)	May 26, 2023 USD ($)	Apr. 27, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2023 EUR (€)	Mar. 06, 2023 USD ($)
Debt Instrument [Line Items]
Short term debt outstanding				$ 511,000,000	$ 8,000,000
Line of credit facility, expiration period	364 days
Interest paid in cash				242,000,000	128,000,000
1.900% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument face amount \| €						€ 550,000,000
Asian Tranche [Member] \| Amendment Two To Syndicated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity		$ 150,000,000
Mexican Tranche [Member] \| Amendment Two To Syndicated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity		$ 150,000,000
1.500% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument face amount \| €						€ 600,000,000
Eight Hundred Million Dollar Three Year Tranche [Member]
Debt Instrument [Line Items]
Debt instrument face amount							$ 800,000,000
Long term debt term							3 years
Proceeds from unsecured debt			$ 100,000,000
Six Hundred Million Dollar Five Year Tranche [Member]
Debt Instrument [Line Items]
Debt instrument face amount							$ 600,000,000
Long term debt term							5 years
Proceeds From Other Investment			$ 300,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, outstanding amount				0	1,000,000
Revolving Credit Facility [Member] \| Old Expiry Date [Member]
Debt Instrument [Line Items]
Line of credit facility expiration date		Jun. 24, 2027
Revolving Credit Facility [Member] \| New Expiry Date [Member]
Debt Instrument [Line Items]
Line of credit facility expiration date		Jun. 24, 2028
Revolving Credit Facility [Member] \| Amendment Two To Syndicated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity		$ 2,700,000,000
Gross amount outstanding under the credit facility				0	0
Amended Syndicated Revolving Credit Facility [Member] \| Amendment Two To Syndicated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility expiration date	Jun. 24, 2024
Current Borrowing Capacity	$ 800,000,000
U.S. Commercial Paper Notes [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity				2,000,000,000
Short term debt outstanding				$ 299,000,000	0
Short term debt weighted average interest rate				5.57%		5.57%
Euro-Commercial Paper Notes [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity \| €						€ 500,000,000
Short term debt outstanding				$ 210,000,000	$ 0
Short term debt weighted average interest rate				4.02%		4.02%