Percentage of debt instrument basis spread on variable rate.

No definition available.

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Namespace Prefix:	mx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

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

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

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+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

+ References

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+ Details

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- Definition

This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Borrowings - Additional Information (Detail) $ in Thousands	Dec. 31, 2025 KRW (₩)	Mar. 26, 2024 KRW (₩)	Jun. 30, 2026 USD ($)	Dec. 30, 2025 KRW (₩)	Sep. 26, 2025 KRW (₩)	Jun. 26, 2025 KRW (₩)	Dec. 16, 2024 KRW (₩)	Dec. 16, 2024 USD ($)	Mar. 26, 2024 USD ($)
Schedule of Capitalization, Long-Term Debt [Line Items]
Loan, Held-in-Portfolio, Principal Outstanding, Total			$ 25,949
Debt instrument, basis spread on variable rate			4.03%
Foreign currency exchange rate, translation	1,434.9		1,541.5
Capex Loans [Member]
Schedule of Capitalization, Long-Term Debt [Line Items]
Loan, Held-in-Portfolio, Principal Outstanding, Total			$ 15,566
Debt Instrument, Maturity Date	Jun. 26, 2035
Debt instrument, interest rate, effective percentage			2.91%
Capex Loans [Member] \| Korea (South), Won
Schedule of Capitalization, Long-Term Debt [Line Items]
Debt instrument, face Amount \| ₩	₩ 23,995,000,000			₩ 9,400,000,000	₩ 5,075,000,000	₩ 9,520,000,000	₩ 38,000,000,000
Working Capital Term Loan [Member]
Schedule of Capitalization, Long-Term Debt [Line Items]
Debt Instrument, Maturity Date		Mar. 26, 2027
Debt instrument, interest rate, effective percentage		4.86%							4.86%
Foreign currency exchange rate, translation		1,340.7	1,541.5				1,432.7	1,432.7	1,340.7
Debt instrument, face Amount			$ 15,566					$ 26,523	$ 29,835
Working Capital Term Loan [Member] \| Korea (South), Won
Schedule of Capitalization, Long-Term Debt [Line Items]
Debt instrument, basis spread on variable rate		1.21%
Debt instrument, face Amount \| ₩		₩ 40,000,000,000