Debt Instrument Term Extension Period

No definition available.

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Namespace Prefix:	smur_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Trade Receivables Securitization Programs

+ References

No definition available.

+ Details

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Namespace Prefix:	smur_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

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

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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.

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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.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

No definition available.

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Debt - Narrative (Details) € in Millions, $ in Millions	1 Months Ended
Debt - Narrative (Details) € in Millions, $ in Millions	Jun. 30, 2026 USD ($) program	Jun. 30, 2026 EUR (€) program	Jun. 29, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 EUR (€)
Debt Instrument [Line Items]
Number of trade receivables securitization programs \| program	3	3
330 Million Receivables Securitization Variable Funding Notes Due 2029
Debt Instrument [Line Items]
Transfers accounted for as secured borrowings, carrying amount \| €		€ 757			€ 749
Remaining borrowing capacity	$ 12			$ 13
$600 million receivables securitization due 2031
Debt Instrument [Line Items]
Transfers accounted for as secured borrowings, carrying amount	1,173			1,043
Remaining borrowing capacity	50			$ 47
$600 million receivables securitization due 2031 \| Secured debt
Debt Instrument [Line Items]
Debt instrument, face amount	$ 600
700 Million Receivables Securitization Due 2027 \| Secured debt
Debt Instrument [Line Items]
Debt instrument, face amount			$ 700
Revolving Credit Facility \| Revolving Credit Facilities Agreement \| Line of Credit
Debt Instrument [Line Items]
Debt extension period	1 year
Borrowing capacity	$ 4,500