Clinical regulatory sales milestones payments and royalities received

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Contract with customer liability deferred revenue recognized on upfront payment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Contract with customer liability revenue recognized value-added tax withheld.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Expense related to milestone payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	algs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Milestone payments and royalties receivable.

+ References

No definition available.

+ Details

Name:	algs_MilestonePaymentsAndRoyaltiesReceivable
Namespace Prefix:	algs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Revenue from licensing agreements.

+ References

No definition available.

+ Details

Name:	algs_RevenueFromLicensingAgreements
Namespace Prefix:	algs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Upfront payment received.

+ References

No definition available.

+ Details

Name:	algs_UpfrontPaymentReceived
Namespace Prefix:	algs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

withholding taxes.

+ References

No definition available.

+ Details

Name:	algs_WithholdingTaxes
Namespace Prefix:	algs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

+ Details

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

- Details

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=algs_AmoytopLicenseAndResearchCollaborationMember
Namespace Prefix:
Data Type:	na
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- Details

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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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- Details

Name:	us-gaap_IncomeTaxAuthorityNameAxis=algs_NetOfChineseWithholdingTaxMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeTaxAuthorityNameAxis=algs_Value-AddedTaxWithheldInChinaMember
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Data Type:	na
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Revenue - Additional Information (Detail) - USD ($)	1 Months Ended						3 Months Ended		9 Months Ended
Revenue - Additional Information (Detail) - USD ($)	Jul. 31, 2026	May 31, 2026	Jan. 31, 2026	May 31, 2025	May 31, 2024	May 31, 2023	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Revenue from licensing agreements							$ 39,000	$ 0	$ 27,817,000	$ 0
Revenue from customers related to upfront payments								700,000		2,000,000
Milestones payments made							0		0
Revenue from contract with customers related to milestone payments							2,800,000	0	5,700,000	0
Amoytop License and Research Collaboration [Member] \| Amoytop [Member]
Upfront payment received				$ 1,000,000	$ 1,500,000	$ 7,000,000	$ 39,000		27,800,000
Clinical regulatory sales milestones payments and royalities received		$ 420,000
Withholding taxes						1,100,000			$ 2,800,000
Revenue from licensing agreements								$ 0		$ 0
Milestones payments made	$ 3,000,000		$ 3,000,000
Revenue from contract with customers related to milestone payments	2,800,000		2,800,000
Amoytop License and Research Collaboration [Member] \| Amoytop [Member] \| Maximum [Member]
Milestone payments and royalties receivable						$ 109,000,000
Amoytop License and Research Collaboration [Member] \| Net of Chinese Withholding Tax [Member] \| Amoytop [Member]
Upfront payment received	25,000,000	$ 25,000,000
Amoytop License and Research Collaboration [Member] \| Value-Added Tax Withheld in China [Member] \| Amoytop [Member]
Value-added tax withheld	$ 200,000		$ 200,000