Commitments and contingencies.

No definition available.

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- Definition

Unrecorded unconditional purchase obligation, to be paid, thereafter

+ References

No definition available.

+ Details

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Namespace Prefix:	amlx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (b)
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in remainder of current fiscal year.

+ References

No definition available.

+ Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025	Oct. 30, 2025
Commitments And Contingencies [Line Items]
Restricted cash	$ 1.0	$ 1.0
Claims settlement amount			$ 6.5
Remaining unconditional purchase obligation	30.0
Purchase obligations to be paid in 12 months	18.8
Purchase obligations to be paid thereafter	11.3
Collateral for Letter of Credit Issued
Commitments And Contingencies [Line Items]
Restricted cash	0.9
Collateral for Corporate Credit Card Program
Commitments And Contingencies [Line Items]
Restricted cash	$ 0.1